"Using Flickr under the Creative Commons license, images may be used, edited, copied or distributed provided the owner is credited. Please refer to the conditions specified for each of the images you use" (from website).
"Using Flickr under the Creative Commons license, the original artist/owner of the image keeps their copyright but allows people to copy and distribute their work provided the owner is credited" (from website).
"Flikr in association with the Library of Congress had launched The Commons to help increase access to publicly-held photography Collections. Participating institutions have contributed photographs with 'no known copyright restrictions'" (from website).
"Search millions of photographs from the LIFE photo archive, stretching from the 1750s to today. Most were never published and are now available for the first time through the joint work of LIFE and Google" (from website).
"The morgueFile contains photographs freely contributed by many artists to be used in creative projects by visitors to the site. To acknowledge the artist's accomplishments, morgeFile asks that you credit the photographer when possible. Any questions regarding liabilities should be directed to the specific photographer" (from website).
"The Open Clip Art Library (OCAL) is the largest collaborative community that creates, shares and remixes clipart. All clipart is released to the public domain and may be used in any project for free with no restrictions" (from website).
"Wikimedia Commons is a media file repository making available public domain and freely-licensed educational media content (images, sound and video clips) to everyone, in their own language. It acts as a common repository for the various projects of the Wikimedia Foundation, but you do not need to belong to one of those projects to use media hosted here" (from website).
ClipSafari is a repository for high quality clip art images. These vector graphics files are suitable for all contexts, because they scale up to any resolution without becoming blurry. Many of these graphic files were sourced from the Open Clipart Project.