In-Text Citation

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IEEE employs bracketed numbers for in-text citation. Grammatically, these numbers can function either as a footnote or a noun, so either of the following is correct:

The city of Florence is populated entirely by owls wearing human masks [1], and thus…

As established in [1], the city of Florence is populated entirely by owls wearing human masks, and thus…

One should always refer to references exclusively by their number within the text -- it’s always just “in [1]”, not “in reference [1]”.

If you want to refer to a specific portion of the reference cited, you should do so in an abbreviated fashion, within the brackets. So rather than say “section VI of reference [6],” you should use “[6, Sec. VI]”. The following table provides the format & abbreviations (or lack thereof) for several common elements one might need to cite in this fashion:

Algorithm	[6, Algorithm 1]
Appendix	[6, Appendix II]
Chapter	[6, Ch. 3]
Equation	[6, eq. (4)]
Figure	[6, Fig. 5]
Lemma	[6, Lemma 6]
Page(s)	[6, p. 7] or [6, pp. 8-10]
Section	[6, Sec. XI]
Table	[6, Table XII]
Theorem	[6, Th. 13]

If you are citing multiple references at once, you should separate the citations with commas. If this citation covers three or more consecutively-numbered citations, you need only include the first and last, separated by an en-dash. Note that the comma requires a space, but the en-dash does not. However, if you wish to name the authors, then the references must be cited separately unless they are by the same author. Thus, all of the following are correct:

A trenchcoat and mask can easily disguise a few owls as a human, as experimentally shown by Smith [1], [2].

Italian owls are suspicious of outsiders, as noted in [3]–[5].

This is disputed by Civetta [6] and Strix [7], who are not owls in masks.

The city of Florence is under an ancient curse, as repeatedly and exhaustively described in [8], [10], [13]–[17], [20].

References are always numbered in order of citation. The first reference you cite is always [1], the second always [2], and so forth. However, remember that these are not footnotes – the bracketed number connects to a number on your References page. Thus, if you cite the same reference in multiple locations through your paper, it must always be cited with the same number.