Citation formats for scholarly writing can take many forms, like author-date, author-page, footnotes, numeric, etc. This time, we decided to shine a light on the most frequently used citation formats with numbers. We compiled a list of the main citation styles with numbers in brackets to help you get started with your paper. Each style includes an explanation of its system, just like reference examples.
The Vancouver style is a numeric citation system used in biomedical, health and other science publications. This style consists of in-text citations indicated with either superscript or bracketed numbers. The same number is used throughout the paper to refer to the same source and given in full in a reference list at the end of the paper. This list is ordered sequentially, not alphabetically.
Check out these Vancouver style resources
Vancouver style examples
An in-text citation in Vancouver style:
A similar study was carried out in 2015(1).
A reference list entry in Vancouver style:
1. Aprile A, Gulino A, Storto M, Villa I, Beretta S, Merelli I, et al. Hematopoietic stem cell function in β-thalassemia is impaired and is rescued by targeting the bone marrow niche. Blood [Internet]. 2020; Available from: http://dx.doi.org/10.1182/blood.2019002721
IEEE (Institute of Electrical and Electronics Engineers) style is based on the Chicago citation style and is used specifically for engineering and science papers. This style uses a numeric citation format, in which a number in square brackets is given as an in-text citation. This number corresponds to a reference list entry at the end of the paper.
Check out these IEEE style resources
IEEE style examples
An in-text citation in IEEE style:
As seen in a multi-camera study ...
A bibliography entry in IEEE style:
 E. Nuger and B. Benhabib, “Multi-Camera Active-Vision for Markerless Shape Recovery of Unknown Deforming Objects,” J. Intell. Rob. Syst., vol. 92, no. 2, pp. 223–264, Oct. 2018.
The Association for Computing Machinery has its own numeric style. This style requires the use of sequential numbers in square brackets for in-text citations, which are later added in full in a reference list at the end of the paper.
Check out these ACM style resources
ACM style examples
An in-text citation in ACM style:
...as seen in a computer-generated holograms for 3D imaging survey .
A bibliography entry in ACM style:
 Erdem Sahin, Elena Stoykova, Jani Mäkinen, and Atanas Gotchev. 2020. Computer-generated holograms for 3D imaging: A survey. ACM Comput. Surv. 53, 2 (2020), 1–35.
#4 Physical Review Letters
The Physical Review Letters style allows both in-text references and footnotes. Each reference must be numbered consecutively (in square brackets) in order of citation, and added to a list at the end of the paper.
Check out these PRL style resources
PRL style examples
An in-text citation in PRL style:
Recent studies ...
A bibliography entry in PRL style:
 P. Gomez, F. Martin, C. Mazzinghi, D. Benedicto Orenes, S. Palacios, and M. W. Mitchell, Phys. Rev. Lett. 124, (2020).
Elsevier journals accept many different types of citation styles, however they have their own numeric style, too. This style, referred as the Standard numbered style in their manuscript, indicates in-text references with numbers in square brackets. These numbers are then added to a reference list in the order in which they appear in the text.
Check out these Elsevier style resources
Elsevier style examples
An in-text citation in Elsevier style:
Similarly, the climate response to ultraviolet irradiation was tested .
A bibliography entry in Elsevier style:
 Z.-N. Xiao, S. Dong, Q. Zhong, Numerical simulation of climate response to ultraviolet irradiation forcing, Adv. Clim. Chang. Res. 10 (2019) 133–142.
Frequently Asked Questions about citation styles with numbers in brackets
1️⃣ What is the most popular citation style with numbers in brackets?
The most popular citation style with numbers in brackets is Vancouver style. This style consists of in-text citations indicated with either superscript or bracketed numbers. The only difference from Vancouver and other styles mentioned above, is that it uses round brackets instead of square brackets.
♨️ Are numbers in brackets italicized?
No, the citation styles mentioned above do not italicize numbers in brackets. Some citation styles, such as Science Magazine style, do italicize numbers. In fact, this style uses round brackets and italicized numbers, making it a very unique citation style. However, most numeric styles with brackets do not italicize numbers.
🧐 Should I use square or round brackets?
Using round or square brackets will depend on the citation style you choose. You can not decide to turn square brackets into round ones, just because you don't like edges. You have to follow the indications of each style, so make sure to confirm if the style of your choosing uses round or square brackets.
🗂️ What journals use citation styles with numbers in brackets?
✍️ Do I have to create a reference list with numbers in brackets manually?
You can, but you don't have to. You can easily create a reference list with numbers in brackets with the BibGuru citation generator. This generator creates the fastest and most accurate citations possible, which will save you time and worries. The best part is, it is completely free!