It’s almost Halloween here in America, so it is time to show people in costumes:
However silly they look in this outfits, the message that the text conveys is serious. When in doubt, add a citation. I got this image here, a site that also has a humorous flow chart for deciding when to cite. Basically, think twice about the content in your scholarly work, and if the idea you are positing came from another source, then include a citation to that source.
Paper Introductions should be full of citations to previous work, demonstrating that the authors have done their homework with a thorough literature search investigating the state of knowledge on this topic. The storyline of the Introduction should focus down from a broad perspective to ever-narrower issues until the specific topic of interest is reach. Sometimes this focusing is fast, just a sentence or two, other times it is several paragraphs. The specific topic should then be rigorously discussed to show that there is a gap in understanding. It should lead to the thesis statement of the unresolved question and why a new study is needed. To get to this point, however, relevant prior studies should be included in this presentation.
Similarly, in the Discussion section of the paper, the new findings should be put into proper perspective with respect to prior studies. That is, this section should also have many citations and a comparison of how the new findings build on those existing findings.
Citation of previous work does not invalidate your contribution to knowledge about that topic. On the contrary, it demonstrates that you are an expert in the fields, are aware that others are working on the same issue, and that your investigation fits within a larger body of work.
Please add citations to relevant work. It’s like raw broccoli: it takes some work to get it down, but once there it’s really good for you.