Our research is built on the collective knowledge obtained from past studies. How to cite other people’s work? Below are three ways of citing published papers, and I’ve ranked them from the most recommended to the least recommended.
1. Add the in-text citation at the end of a statement, without author names in the statement itself. Here is an example:
- Bone morphogenetic protein-2 promotes melanogenesis in cultured neural crest cells by upregulating tyrosinase gene expression (1).
Here the in-text citation is in a numbered format, and it can be easily changed to any format requested by journals.
- Bone morphogenetic protein-2 promotes melanogenesis in cultured neural crest cells by upregulating tyrosinase gene expression (Bilodeau et al., 2001).
No matter how you change the citation format, the statement itself is not affected, and by putting the citation at the end of the statement, it clearly tells the reader that this citation applies to this specific statement. This is the most preferred way of citing references.
2. State who did the previous study.
- Bilodeau et al. (2001) discovered that bone morphogenetic protein-2 promotes melanogenesis in cultured neural crest cells by upregulating tyrosinase gene expression.
- Bilodeau et al. (1) discovered that bone morphogenetic protein-2 promotes melanogenesis in cultured neural crest cells by upregulating tyrosinase gene expression.
When you include the author’s name in the statement, it’s typical to follow the name by the publication year. However, if the journal uses a numbered format for citations, use the number instead of the year. This is also a very commonly used citation method, but many researchers consider this less professional than the first method. This method also makes the sentence unnecessarily longer than the one using the first method. Further, if a paragraph has sentence after sentence written this way, it disrupts the flow of information. The scientific information is interspersed with these author names. If you want to use this method, use it sparingly.
3. Make the reference number part of the statement.
- Reference  shows that bone morphogenetic protein-2 promotes melanogenesis in cultured neural crest cells by upregulating tyrosinase gene expression.
Many of our editors frown on a sentence like this. They would rather see you use the second method. In some fields, such as in biomedical science, this way is used very very rare. The only example I can think of is in parenthesis after a statement like this: xxxxx (reviewed in ). However, in some engineering fields, this way of citing reference is allowed. Journals may have specific instructions on how to cite this way. For example, journals may ask you to not use the word “reference,” so you can just say “ shows…,” “An algorithm in  considers….,” etc. Even for fields that allow this method, we still recommend using the first method for most of the statements in your paper, because it is professional, concise, and easy to be reformatted.
A couple of tips for citing previous studies:
- Describe what the findings are, not what the authors did. If we change our example sentence to “Bilodeau et al. treated cultured neural crest cells with bone morphogenetic protein-2 and assessed melanogenesis and tyrosinase gene expression,” the sentence only describes what those authors did. You’ll have to use another sentence to tell the reader what the authors found, which makes your paper longer. If you don’t follow with a sentence about the findings, this sentence is not that meaningful because your readers will be left with more questions than before they read this sentence.
- When describing work from your own research group, write as if it was from a different group; that is, avoid saying “our previous studies have shown….(1-3).” Some journals do a double-blind peer review, so the journal does not give your names and affiliations to the reviewers. If you have such a sentence in the paper, you give away your identity. Also, if you write a review paper, citing your work the same way as you cite other people’s work helps maintain an objective tone of the paper.