I don’t understand the specifics of it, but unless the work is a piece of common knowledge, you must give a reference for college/school work assignments.

Or have the author’s direct permission to sell or publish the information.

http://www.templetons.com/brad/copymyths.html

****Although, if you purchase a DVD or a Book, you are allowed to sell that particular DVD or Book that you are in ownership of.****

Here is a quote:
Under the copyright laws, the owner of a particular copy of a copyrighted work is generally entitled to resell the particular copy they own. For example, if you purchase a copy of a DVD movie, you are allowed to resell that particular DVD. Copyright protection prevents you from copying the DVD movie and reselling the copies. If you have licensed the right to use a particular copyrighted item, you should review the license and consult with your attorney to determine whether you can resell the item.

http://pages.ebay.com/help/tp/copyrights.html
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By the way – what is the topic? and can I have a copy?
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