A citation...
You must cite a source that you are using if you paraphrase or summarize any of the ideas given in the work AND if you use a direct quote from the resource (word-for-word). Citations are not just for word-for-word quotations; they must be used when you mention any ideas or information from a source.
The Excelsior Online Writing Lab, hosted by Excelsior College, can help you with each step of your writing assignments. Below is the website's navigation tab listing every aspect covered.
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MLA Handbook for Writers of Research Papers by Every discipline has their own citation style, however, every person/professor is different and they may have a preference for a different citation style, or prefer that you use an older format for citations. The books below are examples of the texts that can assist you with properly citing your sources.
Publication Manual of the American Psychological Association by 
The Chicago Manual of Style by 
The Owl/the Purdue Online Writing Lab (Purdue University) can help you with your writing assignments. Below is the website's navigation tab for all aspects covered.
