BibTeX Guide: Managing References and Citations in LaTeX

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:

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

Citation Commands

The commands available depend on whether you use classic BibTeX or BibLaTeX:

BibTeX vs BibLaTeX

BibTeX is the original system. BibLaTeX is the modern replacement. Here are the key differences:

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

Common Errors and Fixes

• "Citation undefined" — You need to run biber (or bibtex) after compiling. The sequence is: pdflatex → biber → pdflatex → pdflatex. Online editors handle this automatically.
• Wrong citation key — Citation keys are case-sensitive. Smith2024 and smith2024 are 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: