Do not link to any source that violates the copyrights of others per contributors' rights and obligations . You can link to websites that display copyrighted works as long as the website has licensed the work, or uses the work in a way compliant with fair use. Knowingly directing others to material that violates copyright may be considered contributory copyright infringement . If there is reason to think a source violates copyright, do not cite it. This is particularly relevant when linking to sites such as Scribd or YouTube , where due care should be taken to avoid linking to material that violates copyright.