Citing references in a paper using IEEE style is fairly straightforward. In general, direct quotations are not preferred in STEM fields. However, it is important to document your sources, especially in a section such as the introduction, in which a review of the existing literature on a given subject is often expected.
References are cited using the reference number enclosed in brackets: , , etc. The organization of the references section depends upon the order in which you refer to sources in the body of your paper. If you cite a single publication more than once, use the original citation number instead of creating a new reference. For example, you might write,
. . . Booske et al. ; however, as mentioned earlier –,  . . .
Where to place citations
In the IEEE style, citations are treated like footnotes (though they are never placed in superscript) or nouns in your sentences. In the example above (“Booske et al. ; however, as mentioned earlier –, ”), the citations are treated like footnotes. You might cite the same sources treating the references as nouns; for example,
. . . was proven incorrect, as demonstrated in –, .
Note that reference citations are placed inside the punctuation.
Because direct quotation is not preferred, you will need to paraphrase your sources. For more information about paraphrasing, see our guide to Quoting and Paraphrasing Sources.