Creative Commons

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Creative Commons
Creative Commons logo
Type 501(c)(3) non-profit organization
Founded 2001
Founder(s) Lawrence Lessig
Key people Catherine Casserly, CEO
Focus(es) Expansion of “reasonable”, flexible copyright
Method(s) Creative Commons license

A sign in a pub in Granada notifies customers that the music they are listening to is freely distributable under a Creative Commons license.

Creative Commons (CC) is a non-profit organization headquartered in Mountain View, California, United States, devoted to expanding the range of creative works available for others to build upon legally and to share.[1] The organization has released several copyrightlicenses known as Creative Commons licenses free of charge to the public. These licenses allow creators to communicate which rights they reserve, and which rights they waive for the benefit of recipients or other creators. An easy-to-understand one-page explanation of rights, with associated visual symbols, explains the specifics of each Creative Commons license. Creative Commons licenses do not replace copyright, but are based upon it. They replace individual negotiations for specific rights between copyright owner (licensor) and licensee, which are necessary under an “all rights reserved” copyright management, with a “some rights reserved” management employing standardized licenses for re-use cases where no commercial compensation is sought by the copyright owner. The result is an agile, low-overhead and low-cost copyright-management regime, profiting both copyright owners and licensees. Wikipedia uses one of these licenses.[2]

The organization was founded in 2001 by Lawrence Lessig, Hal Abelson, and Eric Eldred[3] with the support of Center for the Public Domain. The first article in a general interest publication about Creative Commons, written by Hal Plotkin, was published in February 2002.[4] The first set of copyright licenses was released in December 2002.[5] The founding management team that developed the licenses and built the Creative Commons infrastructure as we know it today included Molly Shaffer Van Houweling, Glenn Otis Brown, Neeru Paharia, and Ben Adida.[6] Matthew Haughey and Aaron Swartz[7] also played a significant role in the early stages of the project. In 2008, there were an estimated 130 million works licensed under the various Creative Commons licenses.[8] As of October 2011, Flickr alone hosts over 200 million Creative Commons licensed photos.[9] Creative Commons is governed by a board of directors and a technical advisory board. Their licenses have been embraced by many as a way for creators to take control of how they choose to share their copyrighted works.

Aim and influence[edit]

Creative Commons Japan Seminar, Tokyo 2007

Creative Commons has been described as being at the forefront of the copyleft movement, which seeks to support the building of a richer public domain by providing an alternative to the automatic “all rights reserved” copyright, and has been dubbed “some rights reserved.”[10] David Berry and Giles Moss have credited Creative Commons with generating interest in the issue of intellectual property and contributing to the re-thinking of the role of the “commons” in the “information age“. Beyond that, Creative Commons has provided “institutional, practical and legal support for individuals and groups wishing to experiment and communicate with culture more freely.”[11]

Creative Commons attempts to counter what Lawrence Lessig, founder of Creative Commons, considers to be a dominant and increasingly restrictive permission culture. Lessig describes this as “a culture in which creators get to create only with the permission of the powerful, or of creators from the past”.[12] Lessig maintains that modern culture is dominated by traditional content distributors in order to maintain and strengthen their monopolies on cultural products such as popular music and popular cinema, and that Creative Commons can provide alternatives to these restrictions.[13][14]



As of 2013, the Board of Creative Commons consists of:[15]

Previous board members include:

CC’s Audit Committee has three members, who are also members of the Board. As of 2013 they are Laurie Racine, Eric Saltzman and Molly Shaffer Van Houweling. Past Audit Committee members include Brian Fitzgerald and Lawrence Lessig[17]


As of 2013, the staff members of Creative Commons include:[16]

Affiliate network[edit]

In 2011, there are more than 100 affiliates working in over 70 jurisdictions to support and promote CC activities around the world.[18]

Creative Commons Asia-Pacific[edit]

South Korea[edit]

Creative Commons Korea (CC Korea) is the affiliated network of Creative Commons in South Korea. In March 2005, CC Korea was initiated by Jongsoo Yoon (in Korean: 윤종수), a Presiding Judge of Incheon District Court, as a project of Korea Association for Infomedia Law (KAFIL). The major Korean portal sites, including Daum and Naver, have been participating in the use of Creative Commons licences. In January 2009, the Creative Commons Korea Association was consequently founded as a non-profit incorporated association. Since then, CC Korea has been actively promoting the liberal and open culture of creation as well as leading the diffusion of Creative Commons in the country.

  • Creative Commons Korea[19]
  • Creative Commons Asia Conference 2010[20]

Supporters of Creative Commons[edit]

Corporate support[edit]

In addition to individual donations, Creative Commons has the following corporate supporters:[21]

Sustainer Level (committed for 5 years)

Investor Level ($25,000 and up)

  • Best Buy
  • Digital Garage
  • Duke University
  • eBay
  • Microsoft Corporation
  • Mountain Equipment Co-op
  • Nike
  • Sage Bionetworks

Types of Creative Commons licenses[edit]

Wanna Work Together? animation by Creative Commons

The second version of the Mayer and Bettle promotional animation explains what Creative Commons is.

Creative Commons licenses consist of four major condition modules: Attribution (BY), requiring attribution to the original author; Share Alike (SA), allowing derivative works under the same or a similar license (later or jurisdiction version); Non-Commercial (NC), requiring the work is not used for commercial purposes; and No Derivative Works (ND), allowing only the original work, without derivatives.[22] These modules are combined to currently form six major licenses of the Creative Commons:[22]

  • Attribution (CC BY)
  • Attribution Share Alike (CC BY-SA)
  • Attribution No Derivatives (CC BY-ND)
  • Attribution Non-Commercial (CC BY-NC)
  • Attribution Non-Commercial Share Alike (CC BY-NC-SA)
  • Attribution Non-Commercial No Derivatives (CC BY-NC-ND)

As of the current versions, all Creative Commons licenses allow the “core right” to redistribute a work for non-commercial purposes without modification. The NC and ND options will make a work non-free according to the Definition of Free Cultural Works.

An additional special license-like contract is the CC0 option, or “No Rights Reserved.”[23] This license dedicates a work to the public domain (or an equivalent status in jurisdictions where a dedication to public domain is not possible). Compared with a “public domain” statement added to the work, a CC0 statement is less ambiguous and achieves the desired effect on a global scale, rather than limited to some jurisdictions.

For software, Creative Commons endorses three free licenses created by other institutions: the BSD License, the CC GNU LGPL license, and the CC GNU GPL.[24][25]

Use of Creative Commons licenses[edit]

Creative Commons maintains a content directory wiki of organizations and projects using Creative Commons licenses.[26] On its website CC also provides case studies of projects using CC licenses across the world.[27] CC licensed content can also be accessed through a number of content directories and search engines (see CC licensed content directories).

Jurisdiction ports[edit]

Countries to which Creative Commons licenses have been ported (green) or are being ported (blue)

The original non-localized Creative Commons licenses were written with the U.S. legal system in mind, so the wording could be incompatible within different local legislations and render the licenses unenforceable in various jurisdictions. To address this issue, Creative Commons has started to port the various licenses to accommodate local copyright and private law. As of May 2010, there are 52 jurisdiction-specific licenses, with 9 other jurisdictions in drafting process, and more countries joining the worldwide project.[28]

For the newly released version 4.0 of the Creative Commons licenses, they are generic licenses that are applicable to most jurisdictions and do not usually require ports.[29][30][31]


General criticism[edit]

CC some rights reserved

Péter Benjamin Tóth, a director at the Hungarian royalty collector bureau ARTISJUS, asserts that Creative Commons’ objectives are already well served by the current copyright system, and that Creative Commons’ “some rights reserved” slogan, as opposed to the “all rights reserved” principle, creates a false dichotomy. “Copyright provides a list of exclusive rights to the rightholder, from which he decides which ones he wishes to ‘sell’ or grant and which to retain. The ‘some rights reserved’ concept is therefore not an alternative to, but rather the very nature of classical copyright.”[32] Other critics fear that Creative Commons could erode the copyright system over time[33] or allow “some of our most precious resources — the creativity of individuals — to be simply tossed into the commons to be exploited by whomever has spare time and a magic marker.”[34] Some critics question whether Creative Commons licenses are useful for artists, and suggest that Creative Commons primarily serves a “remix culture” and fails to meet the real needs of financial compensation and recognition of artists[34] or worry that the lack of rewards for content producers will dissuade artists from publishing their work.[35]

Some critics contend that the Creative Commons licensing system dissuades content producers from coordinating efforts to modernize copyright law.[33]

Creative Commons founder Lawrence Lessig counters that copyright laws have not always offered the strong and seemingly indefinite protection that today’s law provides.[36] Rather, the duration of copyright used to be limited to much shorter terms of years, and some works never gained protection because they did not follow the now-abandoned compulsory format.[36]

Another critic questions whether Creative Commons is the commons that it purports to be, given that at least some restrictions apply to people’s ability to use the resources within the common field.[35] This is restricted entirely within the private rights of others and has nothing to do with rights shared by all.[37][clarification needed] Creative Commons also does not define “creativity” or what aspects a work requires in order to become part of the commons.[35]

Critics such as Giles Moss argue that the founding of Creative Commons is not the proper mechanism for creating a commons of original content.[37] Rather, a commons should be created, and its presence preserved, through the political process and political activism, not through lawyers “writing down new rules”.[37]

License proliferation and incompatibility[edit]

Critics have also argued that Creative Commons worsens license proliferation, by providing multiple licenses that are incompatible.[38] The Creative Commons website states, “Since each of the six CC licenses functions differently, resources placed under different licenses may not necessarily be combined with one another without violating the license terms.”[39] Works licensed under incompatible licenses may not be recombined in a derivative work without obtaining permission from the copyright owner.[40][41][42] Some worry that “without a common legal framework, works which inadvertently mix licenses may become unshareable.”[43]

The compatibility issue is especially relevant because the most frequently used licenses, the non-free “non-commercial” licenses (CC BY-NC-SA or CC BY-NC-ND) and the open attribution-share-alike license (CC BY-SA, used, e. g., by Wikipedia) cannot be combined.

License misuse[edit]

Creative Commons guiding the contributors. This image is a derivative work of Liberty Leading the People by Eugène Delacroix.

Creative Commons is only a service provider for standardized license text, not a party in any agreement. Abusive users could brand the copyrighted works of legitimate copyright holders with Creative Commons licenses and re-upload these works to the internet. No central database of Creative Commons works is controlling all licensed works and the responsibility of the Creative Commons system rests entirely with those using the licences.[44] This situation is, however, not specific to Creative Commons. All copyright owners must individually defend their rights and no central database of copyrighted works or existing license agreements exists. The United States Copyright Office does keep a database of all works registered with it, but absence of registration does not imply absence of copyright.

Although Creative Commons offers multiple licenses for different uses, some critics suggest that the licenses still do not address the differences among the media or among the various concerns that different authors have.[35] For example, one critic points out that documentary filmmakers could have vastly different concerns from those held by a software designer or a law professor.[35] Additionally, people wishing to use a Creative Commons-licensed work would have to determine if their particular use is allowed under the license or if they need additional permission.[35]

Lessig wrote that the point of Creative Commons is to provide a middle ground between two extreme views of copyright protection—one demanding that all rights be controlled, and the other arguing that none should be controlled.[36] Creative Commons provides a third option that allows authors to pick and choose which rights they want to control and which they want to grant to others.[36] The multitude of licenses reflects the multitude of rights that can be passed on to subsequent creators.[36]

Criticism of requirements[edit]

Many[who?] criticize that four out of the six Creative Commons licenses are neither free nor open because of the restrictions they place on reuse, with the definition of open being “A piece of content or data is open if anyone is free to use, reuse, and redistribute it — subject only, at most, to the requirement to attribute and share-alike.”[45]


All current non-CC0 licenses require attribution, which can be inconvenient for works based on multiple other works.[46]

The Free Software Foundation[edit]

Some[which?] of Creative Commons licenses have been denounced by FSF founder Richard Stallman because, he says, they “do not give everyone […] minimum freedom” “to share, noncommercially, any published work”.[47] Those licenses have since been “retired” by Creative Commons.

Mako Hill asserts that Creative Commons fails to establish a “base level of freedom” that all Creative Commons licenses must meet, and with which all licensors and users must comply. “By failing to take any firm ethical position and draw any line in the sand, CC is a missed opportunity…. CC has replaced what could have been a call for a world where ‘essential rights are unreservable’ with the relatively hollow call for ‘some rights reserved.” Some critics fear that Creative Commons’ popularity may detract from the more stringent goals of other free content organizations.[38]

Other criticism of the non-commercial license[edit]

Other critics, such as Erik Möller, raise concerns about the use of Creative Commons’ non-commercial license. Works distributed under the Creative Commons Non-Commercial license are not compatible with many open-content sites, including Wikipedia, which explicitly allow and encourage some commercial uses. Möller explains that “the people who are likely to be hurt by an -NC license are not large corporations, but small publications like weblogs, advertising-funded radio stations, or local newspapers.”[48]

Lessig responds that the current copyright regime also harms compatibility and that authors can lessen this incompatibility by choosing the least restrictive license.[49] Additionally, the non-commercial license is useful for preventing someone else from capitalizing on an author’s work when the author still plans to do so in the future.[49]


The maintainers of Debian, a GNU and Linux distribution known for its rigid adherence to a particular definition of software freedom,[50] rejected the Creative Commons Attribution License prior to version 3 as incompatible with the Debian Free Software Guidelines (DFSG) due to the license’s anti-DRM provisions (which might, due to ambiguity, be covering more than DRM) and its requirement that downstream users remove an author’s credit upon request from the author.[51] However, version 3.0 of the Creative Commons licenses addressed these concerns[52] and is considered to be compatible with the DFSG.[53]

Creative Commons licensed works in court[edit]

Some works licensed using Creative Commons licenses have been involved in several court cases.[54] Creative Commons itself was not a party to any of these cases; they only involved licensors or licensees of Creative Commons licenses. When the cases went as far as decisions by judges (that is, they were not dismissed for lack of jurisdiction or were not settled privately out of court), they have all validated the legal robustness of Creative Commons public licenses. Here are some notable cases:

Dutch tabloid[edit]

In early 2006, podcaster Adam Curry sued a Dutch tabloid who published photos from Curry’s Flickr page without Curry’s permission. The photos were licensed under the Creative Commons Non-Commercial license. While the verdict was in favor of Curry, the tabloid avoided having to pay restitution to him as long as they did not repeat the offense. Professor Bernt Hugenholtz, main creator of the Dutch CC license and director of the Institute for Information Science of the University of Amsterdam, commented, “The Dutch Court’s decision is especially noteworthy because it confirms that the conditions of a Creative Commons license automatically apply to the content licensed under it, and bind users of such content even without expressly agreeing to, or having knowledge of, the conditions of the license.”[55][56][57][58]

Virgin Mobile[edit]

In 2007, Virgin Mobile Australia launched an Australian bus stop ad campaign promoting their cellphone text messaging service using the work of amateur photographers who uploaded their work to Flickr using a Creative Commons-BY (Attribution) license. Users licensing their images this way freed their work for use by any other entity, as long as the original creator was attributed credit, without any other compensation required. Virgin upheld this single restriction by printing a URL leading to the photographer’s Flickr page on each of their ads. However, one picture, depicting 15 year-old Alison Chang at a fund-raising carwash for her church,[59] caused some controversy when she sued Virgin Mobile. The photo was taken by Alison’s church youth counselor, Justin Ho-Wee Wong, who uploaded the image to Flickr under the Creative Commons license.[59] In 2008, the case (concerning personality rights rather than copyright as such) was thrown out of a Texas court for lack of jurisdiction.[60][61]

SGAE vs Fernández[edit]

In the fall of 2006, collecting society Sociedad General de Autores y Editores (SGAE) in Spain sued Ricardo Andrés Utrera Fernández, owner of a disco bar located in Badajoz who played CC-licensed music. SGAE argued that Fernández should pay royalties from public performance of music during the period between November 2002 and August 2005. The Lower Court rejected the collecting society’s claims because the owner of the bar proved that the music he was using was not managed by the society.[62]

GateHouse Media, Inc. vs. That’s Great News, LLC[edit]

On June 30, 2010 GateHouse Media filed a lawsuit against That’s Great News. GateHouse Media owns a number of local newspapers, including Rockford Register Star, which is based in Rockford, Illinois. That’s Great News makes plaques out of newspaper articles and sells them to the people featured in the articles.[63] GateHouse sued That’s Great News for copyright infringement and breach of contract. GateHouse claimed that TGN violated the non-commercial and no-derivative works restrictions on GateHouse Creative Commons licensed work when TGN published the material on its website. The case was settled on August 17, 2010, though the settlement was not made public.[63][64]

See also[edit]


  1. ^ “Frequently Asked Questions”. Creative Commons. Retrieved 20 December 2011. 
  2. ^ “Wikimedia Foundation Terms of Use”. Retrieved June 11, 2012. 
  3. ^ “Creative Commons: History”. Retrieved 2011-10-09. 
  4. ^ Plotkin, Hal (2002-2-11). “All Hail Creative Commons Stanford professor and author Lawrence Lessig plans a legal insurrection”. Retrieved 2011-03-08. 
  5. ^ “History of Creative Commons”. Retrieved 2009-11-08. 
  6. ^ Haughey, Matt (2002-09-18). “Creative Commons Announces New Management Team”. Retrieved 2013-05-07. 
  7. ^ Lessig, Lawrence (2013-01-12). “Remembering Aaron Swartz”. Retrieved 2013-05-07. 
  8. ^ “History of Creative Commons”. Retrieved 2010-02-05. 
  9. ^ Kremerskothen, Kay (5 October 2011). “200 million Creative Commons photos and counting!”. Flickr Blog. Retrieved 20 December 2011. 
  10. ^ Broussard, Sharee L. (September 2007). “The copyleft movement: creative commons licensing”. Communication Research Trends. 
  11. ^ Berry, David (15 July 2005). “On the “Creative Commons”: a critique of the commons without commonalty”. Free Software Magazine. Retrieved 20 December 2011. 
  12. ^ Lessig, Lawrence (2004). Free Culture (PDF). New York: Penguin Press. p. 8. ISBN 1-59420-006-8. 
  13. ^ Ermert, Monika (2004-06-15). “Germany debuts Creative Commons”. The Register. 
  14. ^ Lessig, Lawrence (2006). “Lawrence Lessig on Creative Commons and the Remix Culture” (mp3). Talking with Talis. Archived from the original on 2008-02-05. Retrieved 2006-04-07. 
  15. ^ “Board of Directors – Creative Commons”. Retrieved 12 October 2013. 
  16. ^ a b “Staff – Creative Commons”. Retrieved 12 October 2013. 
  17. ^ “Board of Directors – Creative Commons”. Retrieved 2013-01-13. 
  18. ^ “CC Affiliate Network”. Creative Commons. Archived from the original on 8 January 2011. 
  19. ^ “Creative Commons Korea”. Retrieved 20 December 2011. 
  20. ^ “CC Asia Conference 2010”. Creative Commons. 21 July 2010. Retrieved 20 December 2011. 
  21. ^ “Our Supporters”. Retrieved 2013-04-11. 
  22. ^ a b “Licenses – Creative Commons”. Retrieved 2009-07-20. 
  23. ^ “About CC0 — “No Rights Reserved””. Retrieved 2009-07-20. 
  24. ^ “Creative Commons GNU LGPL”. Archived from the original on 2009-06-22. Retrieved 2009-07-20. 
  25. ^ “Creative Commons GNU GPL”. Archived from the original on 2009-06-22. Retrieved 2009-07-20. 
  26. ^ “Content Directories”. Retrieved 2009-04-24. 
  27. ^ “Case Studies”. Creative Commons. Retrieved 20 December 2011. 
  28. ^ “Worldwide”. Creative Commons. Archived from the original on 21 December 2009. 
  29. ^ “CC 4.0, an end to porting Creative Commons licences?”. TechnoLlama. 25 September 2011. Retrieved 11 August 2013. 
  30. ^ Doug Whitfield (5 August 2013). “Music Manumit Lawcast with Jessica Coates of Creative Commons”. YouTube. Retrieved 11 August 2013. 
  31. ^ “What’s new in 4.0?”. Creative Commons. 2013. Retrieved 26 November 2013. 
  32. ^ Tóth, Péter Benjamin (2009). Creative Humbug. Indicare Project 
  33. ^ a b John Dvorak (July 2005). Creative Commons Humbug. PC Magazine 
  34. ^ a b Schaeffer, Maritza (2009). “Note and Comment: Contemporary Issues in the Visual Art World: How Useful are Creative Commons Licenses?”. Journal of Law and Policy. 
  35. ^ a b c d e f Elkin-Koren, Niva (2006). “Exploring Creative Commons: A Skeptical View of a Worthy Pursuit”. The Future of the Public Domain (P. Bernt Hugenholtz and Lucie Guibault, eds.). 
  36. ^ a b c d e Lessig, Lawrence (2004). “The Creative Commons”. 65 Mont. L. Rev. 1. 
  37. ^ a b c Moss, Giles (2005). “On the Creative Commons: A Critique of the Commons Without Commonality”. Free Software Magazine. 
  38. ^ a b Benjamin Mako Hill (29 July 2005). “Towards a Standard of Freedom: Creative Commons and the Free Software Movement”. 
  39. ^ CC Learn Explanations: Remixing OER: A guide to License Compatibility. Creative Commons CC Learn. Retrieved 29 November 2010 
  40. ^ “Can I combine two different Creative Commons licensed works? Can I combine a Creative Commons licensed work with another non-CC licensed work?”. FAQ. Creative Commons. Retrieved 16 September 2009. 
  41. ^ “Creative Commons Attribution ShareAlike 3.0 Unported”. Creative Commons. Retrieved 18 November 2009. 
  42. ^ “Creative Commons Attribution Share-Alike 3.0 Unported”. Creative Commons. Retrieved 18 November 2009. 
  43. ^ Michael Fitzgerald (December 2005). “Copyleft Hits a Snag”. 
  44. ^ Orlowski, Andrew (July 2009). “The Tragedy of the Creative Commons”. 
  45. ^ “Open Definition”. 
  46. ^ Paley, Nina (2010-03-04). “The Limits of Attribution”. Nina Paley’s Blog. Retrieved 2013-01-30 
  47. ^ Stallman, Richard M. “Fireworks in Montreal”. FSF Blogs. Retrieved 18 November 2009. 
  48. ^ Erik Moeller (2006). “The Case for Free Use: Reasons Not to Use a Creative Commons -NC License”. Open Source Jahrbuch. 
  49. ^ a b Lessig, Lawrence (2005). “CC in Review: Lawrence Lessig on Important Freedoms”. Creative Commons. 
  50. ^ “Debian Social Contract”. Debian. 2004-04-26. Retrieved 2013-11-26. 
  51. ^ Evan Prodromou (3 April 2005). “Summary of Creative Commons 2.0 Licenses”. debian-legal (mailing list). 
  52. ^ Garlick, Mia (2007-02-23). “Version 3.0 Launched”. Creative Commons. Retrieved 2007-07-05. 
  53. ^ “The DFSG and Software Licenses – Creative Commons Share-Alike (CC-SA) v3.0”. Debian Wiki. Retrieved 2009-03-16. 
  54. ^ “Creative Commons Case Law”. Retrieved 31 Aug 2011. 
  55. ^ “Creative Commons license upheld by court”. Retrieved 2012-12-24. 
  56. ^ Digital Copyright and the Consumer Revolution: Hands Off My Ipod – Matthew Rimmer – Google Böcker. Retrieved 2012-12-24. 
  57. ^ “Creative Commons License Upheld by Dutch Court”. Groklaw. 2006-03-16. Retrieved 2006-09-02. 
  58. ^ “Creative Commons Licenses Enforced in Dutch Court”. Retrieved 31 Aug 2011. 
  59. ^ a b Cohen, Noam. “Use My Photo? Not Without Permission.”. New York Times. Retrieved 2007-09-25. “One moment, Alison Chang, a 15-year-old student from Dallas, is cheerfully goofing around at a local church-sponsored car wash, posing with a friend for a photo. Weeks later, that photo is posted online and catches the eye of an ad agency in Australia, and the altered image of Alison appears on a billboard in Adelaide as part of a Virgin Mobile advertising campaign.” 
  60. ^ Evan Brown (January 22, 2009). “No personal jurisdiction over Australian defendant in Flickr right of publicity case”. Internet Cases, a blog about law and technology. Archived from the original on 2011-07-13. Retrieved 25 September 2010. 
  61. ^ “Lawsuit Against Virgin Mobile and Creative Commons – FAQ”. Retrieved 31 Aug 2011. 
  62. ^ Mia Garlick (March 23, 2006). “Spanish Court Recognizes CC-Music”. Creative Commons. Retrieved 25 September 2010. 
  63. ^ CMLP Staff (August 5, 2010). “GateHouse Media v. That’s Great News”. Citizen Media Law Project. Retrieved 20 April 2012. 


External links[edit]

This article uses material from the Wikipedia article Creative Commons, which is released under the Creative Commons Attribution-Share-Alike License 3.0.