The license used in the CFD-Wiki grants free access to the content in the same sence as open-source software is often made available under a GPL license. Hence, CFD-Wiki content can be copied, modified, and redistributed as long as the new version grants the same freedom to others and acknowledges the authors of the article used (a direct link back to the article satisfies our author credit requirement). A CFD-Wiki article therefore will remain free forever and can be used by anybody subject to certain restrictions, most of which serve to ensure that freedom.
The only official and legally binding license statement for text in the CFD-Wiki is:
- Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License". Content in CFD-Wiki is covered by certain disclaimers.
Source-code and software available in the CFD-Wiki is not covered by this license. Instead, source-code and software is either public-domain and available freely without any restrictions or, if so specified in the source-code, available under the Gnu General Public License (GPL).
Using content from CFD-Wiki - rights and obligations
If you want to use text from the CFD-Wiki in your own books, articles, web sites or other publications, you can do so, but you have to follow the GFDL. If you create a derivative works by changing or adding content you must ensure that:
- Your documents in turn are licensed under GFDL
- You acknowledge the authorship of the article, preferably with a direct link to the the CFD-Wiki here at CFD Online (see the example below).
- You provide access to a transparent copy of your documents. A transparent copy is a copy which is easily available electronically.
Here is an example of a statment which you can use which would fullfill the first two points above:
This document is licensed under the <a href="http://www.gnu.org/copyleft/fdl.html"> GNU Free Documentation License</a>. It uses material from the <a href="http://www.cfd-online.com/Wiki/Page_title">CFD-Wiki article "Page title" at <a href="http://www.cfd-online.com/">CFD Online</a>.
The "Page title" and the page URL should of course be substituted accordingly.
Contributing content to CFD-Wiki - rights and obligations
If you contribute material to the CFD-Wiki, you thereby license it to the public under the GFDL (with no invariant sections, front-cover texts, or back-cover texts). In order to contribute, you therefore must be in a position to grant this license, which means that either:
- You own the copyright to the material, for instance because you produced it yourself, or:
- You acquired the material from a source that allows the licensing under GFDL, for instance because the material is in the public domain or is itself published under GFDL.
If you are the original author you retain the copyright to your own material. You can later republish and relicense it in any way you like. However, you can never retract the GFDL license for the versions you placed here: that material will remain under GFDL forever. If you incorporate external GFDL materials you need to acknowledge the authorship and provide a link back to the location of the original copy.
Using material copyrighted by someone else
If you want to use material from someone else you should first ask the copyright holder for permission to release it under the GFDL. See the copyright permission letter for an example of how to ask a copyright holder to grant us a license to use their work under the terms of the GFDL. Never use materials that infringe the copyrights of others. This could create legal liabilities and seriously hurt the project. If in doubt, write it yourself. Note that copyright law governs the creative expression of ideas, not the ideas or information themselves. Therefore, it is perfectly legal to read an article or other work, reformulate it in your own words, and submit it to the CFD-Wiki.
Linking to copyrighted works is usually not a problem, as long as you have made a reasonable effort to determine that the page in question is not violating someone else's copyright. If it does, please do not link to the page. Whether such a link is contributory infringement is currently being debated in the courts, but in any case, linking to a site that illegally distributes someone else's work sheds a bad light on us.
Resolving copyright violations
We take copyrights seriously and will do all in our power to ensure that CFD-Wiki does not violate anyones rights. If you are the owner of content that is being used on CFD-Wiki without your permission, then you may request that the content be immediately removed from CFD-Wiki. To do this go to the Wiki discussion forum and post a message describing the problem. Start the message subject with "Copyright violation:" and provide a link to the page which violates your copyright. Some form of evidence to support your claim of ownership is also appreciated, preferably a link to the original source of the material. A Wiki administrator will review your report as soon as possible and if a copyright violation has occured we will remove the content immediately.
This page was originally based on Wikipedias copyright page.