We should cite whenever we have directly quoted or paraphrased the work of someone else. You should also cite a source if you are including an image, chart or graph that in not originally yours. In college and always, citing is greatly encouraged whenever you are writing a research paper.
APA citation style is the citation style of the American Psychological Association. It is covered extensively in the Publication Manual of the American Psychological Association.
The Online Writing Lab (OWL) that is made available through Purdue University is also a great resource for APA citation style formatting and tips.
With so many articles available through electronic databases it is important to know how to cite these electronically-accessed articles. The American Psychological Association (APA) required that electronic articles are differentiated from print articles on the References page.
According to APA citation style, citations to electronic resources should include a DOI, however if no DOI exists for an electronic resource, the URL may instead be used.
An electronic citation for a source with a DOI will look like this on the References page:
Lastname, F. (year). Article title. Journal Title, volume(issue). page range. doi: ###
Belter, R. W., & du Pre, A. (2009). A strategy to reduce plagiarism in an undergraduate course. Teaching of Psychology, 36(4), 257-261. doi: 10.1080/00986280903173165
An electronic citation for a source without a DOI will look like this on the References page:
Lastname, F. (year). Article title. Journal Title, volume(issue). page range. Retrieved from URL
Case, D. O., & Higgins, G. M. (2000). How can we investigate citation behavior? A study of reasons for citing literature in communication. Journal of the American Society for Information Science, 51(7), 635-45. Retrieved from http://0-search.ebscohost.com.library.daemen.edu/login.aspx?direct=true&AuthType=cookie,ip,uid&db=eric&AN=EJ606760&site=ehost-live&scope=site
NOTE 1: Whenever a source on the Reference page ends with a DOI or a URL, the entry will end without a period even though Reference page entries to print sources will end in a period.
NOTE 2: DOIs are tricky to find. They may show up in the header or footer of the PDF you are looking at or they may be referred to in the database. Though students should make an effort to find the DOI for the resource in question, if one simply cannot be found, do use the URL (Web address).
NOTE 3: When compiling your Reference page, if your sources do contain either a DOI or a URL, please do not add returns or extra spaces in the middle of the DOI or URL string to control where a line will end. The reason why DOIs and URLs are used in your citation is to provide easy access to your source. Part of the ease-of-access is to allow reader to copy your DOI or URL string and paste it into a Web browser and adding extra spaces will not allow a reader to properly copy the string.