BibTeX Guide: Managing References and Citations in LaTeX
April 8, 2026
BibTeX is the standard way to manage references in LaTeX. You maintain a single .bib file with all your sources, and LaTeX automatically formats citations and generates your bibliography. This guide covers the .bib file format, citation commands, and the key differences between BibTeX and BibLaTeX.
The .bib File Format
A .bib file contains entries like this:
@article{vaswani2017attention,
title = {Attention Is All You Need},
author = {Vaswani, Ashish and Shazeer, Noam and Parmar, Niki
and Uszkoreit, Jakob and Jones, Llion and Gomez,
Aidan N. and Kaiser, Lukasz and Polosukhin, Illia},
journal = {Advances in Neural Information Processing Systems},
volume = {30},
year = {2017},
}
@book{knuth1984texbook,
title = {The {\TeX}book},
author = {Knuth, Donald E.},
publisher = {Addison-Wesley},
year = {1984},
}
@inproceedings{he2016deep,
title = {Deep Residual Learning for Image Recognition},
author = {He, Kaiming and Zhang, Xiangyu and Ren, Shaoqing
and Sun, Jian},
booktitle = {IEEE Conference on Computer Vision and Pattern
Recognition (CVPR)},
pages = {770--778},
year = {2016},
}Each entry has a type (@article, @book, @inproceedings, etc.), a citation key (e.g., vaswani2017attention), and fields. The citation key is what you use in your LaTeX document with \cite{}.
Common Entry Types
| Type | Use For | Required Fields |
|---|---|---|
@article | Journal papers | author, title, journal, year |
@inproceedings | Conference papers | author, title, booktitle, year |
@book | Books | author/editor, title, publisher, year |
@misc | Websites, preprints, other | author, title, year, note/url |
@phdthesis | PhD dissertations | author, title, school, year |
@techreport | Technical reports | author, title, institution, year |
Skip manual BibTeX entry writing
Paste a DOI, arXiv ID, or paper title into Underleaf's citation generator and get a properly formatted BibTeX entry instantly.
Try Citation GeneratorCitation Commands
The commands available depend on whether you use classic BibTeX or BibLaTeX:
| Command | Output (example) | Package |
|---|---|---|
\cite{key} | [1] or (Author, Year) | Both |
\textcite{key} | Author (Year) | BibLaTeX only |
\parencite{key} | (Author, Year) | BibLaTeX only |
\citet{key} | Author (Year) | natbib |
\citep{key} | (Author, Year) | natbib |
BibTeX vs BibLaTeX
BibTeX is the original system. BibLaTeX is the modern replacement. Here are the key differences:
| Feature | BibTeX | BibLaTeX |
|---|---|---|
| Backend | bibtex | biber (recommended) |
| Unicode support | Limited | Full |
| Citation styles | .bst files (hard to customize) | LaTeX macros (easy to customize) |
| Multiple bibliographies | Requires extra packages | Built-in |
| URL/DOI fields | Not standard | Native support |
| Journal compatibility | Widely supported | Growing, but some journals still require BibTeX |
For new projects, use BibLaTeX with biber unless your journal specifically requires classic BibTeX. BibLaTeX is more flexible, handles Unicode names correctly, and is easier to customize.
Setting Up BibLaTeX
% In your preamble
\usepackage[
style=authoryear, % or: numeric, ieee, apa, etc.
backend=biber,
sorting=nyt, % sort by name, year, title
maxbibnames=99, % show all authors in bibliography
maxcitenames=2, % truncate in-text after 2 authors
]{biblatex}
\addbibresource{references.bib}
% At the end of your document
\printbibliographyCommon Errors and Fixes
- "Citation undefined" — You need to run biber (or bibtex) after compiling. The sequence is:
pdflatex → biber → pdflatex → pdflatex. Overleaf handles this automatically. - Wrong citation key — Citation keys are case-sensitive.
Smith2024andsmith2024are different keys. - Special characters in titles — Wrap words you want to keep capitalized in braces:
title = {{B}ayesian {N}etworks}. BibTeX lowercases titles by default in some styles. - Missing fields — If a reference shows as "[?]" or appears incomplete, check that all required fields are present in your .bib entry.
- Encoding errors — If you have authors with accented names (e.g., José, Müller), use BibLaTeX with biber. Classic BibTeX struggles with non-ASCII characters.
Citing arXiv Preprints
arXiv papers aren't published in journals, so use @misc or @article with the eprint field:
@misc{devlin2019bert,
title = {{BERT}: Pre-training of Deep Bidirectional
Transformers for Language Understanding},
author = {Devlin, Jacob and Chang, Ming-Wei and Lee,
Kenton and Toutanova, Kristina},
year = {2019},
eprint = {1810.04805},
archiveprefix = {arXiv},
primaryclass = {cs.CL},
}Generate arXiv citations automatically
Enter an arXiv ID and Underleaf generates the complete BibTeX entry with all metadata. See our guide to citing arXiv papers for more details.
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