The Purdue Owl's citation guides are extensive and great resources!
Citations provide basic information about an information source that allows you or others to locate the same source again. The information source may be a book, journal article, webpage, radio broadcast, etc. Although the information needed to locate a journal article vs. a webpage (or a book vs. a radio broadcast) may vary, some basic information such as who, what, when, and where should be made available in the citation (see bulleted list of Basic Components of an Article Citation below).
When writing papers, it is essential to cite your sources, meaning that you must say where the information came from . If you do not cite your sources, you may be guilty of plagiarism. When in doubt if you should cite a source, err on the side of precaution and note where the information came from.
Basic Components of an Article Citation
Many, but not all, online resources have a DOI (digital object identifier). These numbers are specific to an online resource, so your professor (or anybody) can use the DOI to find the online source's citation, or possibly the full text. Learn more about DOIs in the:
How do you locate a DOI?
Help, I Can't Find a DOI:
Not every online article, document, report, book, etc. has a DOI. If you've tried the above steps, and haven't found a DOI, you've done your due diligence. You can then refer to your APA Style Guide to find out how to properly cite the source when there is no DOI.
Why bother with a citation management system? See Cite Faster: Use Zotero (2-minute video). This video will give you a great idea of how useful Zotero is!
Check out this full library guide to using Zotero to learn more: