How to build a LaTeX reference list — BibTeX, biblatex, and the compile order

Every LaTeX reference list has the same three moving parts: a set of records (usually a .bib file), a program that formats them (BibTeX or Biber), and a command in the document that prints the result. Almost every broken bibliography is a mismatch between those three rather than a mistake inside any one of them.

Here are the two setups that work with a .bib file, how to choose between them, and the compile order that makes the list actually appear — plus a third route, at the end, for when you do not want a .bib file at all.

The two routes, and how to pick

	Route 1: BibTeX	Route 2: biblatex + Biber
Load the records	\bibliography{refs} (no extension)	\addbibresource{refs.bib} (with extension)
Print the list	same command	\printbibliography
Choose the style	\bibliographystyle{plain} — a .bst file	a package option: style=authoryear
Formatting program	bibtex	biber

Pick Route 1 if a publisher handed you a class or a .bst file — IEEEtran, acmart, elsarticle, most journal templates. IEEEtran and elsarticle ship BibTeX styles only; acmart ships biblatex styles as well, but its own manual calls that support experimental and says ACM’s TAPS production system does not accept it. Arguing with the template costs more than it saves.

Pick Route 2 if the choice is yours. Styles are package options instead of files you have to hunt for, sorting handles non-ASCII names properly, and you can print several bibliographies from one source (per chapter, or primary sources separately).

One .bib file feeds either route, but do not mix the commands. \bibliographystyle belongs to Route 1 and \printbibliography to Route 2.

Route 1 — BibTeX, in four commands

Two files. refs.bib:

@inproceedings{vaswani2017attention,
  author    = {Vaswani, Ashish and Shazeer, Noam and Parmar, Niki},
  title     = {Attention Is All You Need},
  booktitle = {Advances in Neural Information Processing Systems},
  year      = {2017}
}

main.tex:

\documentclass{article}
\begin{document}

Attention-based models replaced recurrence for sequence transduction
\cite{vaswani2017attention}.

\bibliographystyle{plain}
\bibliography{refs}     % refs.bib, written without the extension

\end{document}

Then run, in this order:

pdflatex main   # writes main.aux: \citation{...}, \bibdata{refs}, \bibstyle{plain}
bibtex   main   # reads main.aux, pulls the cited entries from refs.bib, writes main.bbl
pdflatex main   # pulls in main.bbl — the list appears, in-text numbers are still [?]
pdflatex main   # the numbers resolve

Two details do most of the damage. The second command takes the job name (main), not main.tex and not refs — BibTeX is a separate program that runs against the .aux file, not against your source. And LaTeX has to run twice afterwards: once to pull in the list BibTeX generated, once to number the citations that the list just defined.

latexmk -pdf main.tex runs the whole chain and repeats until the output stops changing; Overleaf and most editor build buttons do the same thing. Run the four commands by hand once anyway. When the build button fails, the log you need is BibTeX’s own (main.blg), and knowing which pass produced it saves an hour.

Why the list is empty

What you see	What went wrong
[?] where the citation should be	LaTeX has not run twice since BibTeX
No bibliography at all	BibTeX never ran, or ran on the wrong name
I found no \citation commands	the .aux holds no \citation — the LaTeX pass aborted before writing them, or nothing cites anything (with no .aux at all the message is I couldn't open file name `main.aux')
I couldn't open database file refs.bib	BibTeX searched and did not find it — wrong path or wrong name
An entry sits in refs.bib but never prints	nothing cites it
Citation undefined after a full clean run	the key in \cite does not match the key in the entry

The fifth row is worth stating on its own: BibTeX prints only what you cite. A 200-entry .bib in a paper that cites twelve of them produces a list of twelve. When you want the whole file printed — a reading list, an annotated bibliography — put \nocite{*} before \bibliography{refs}.

The cite commands: natbib in practice

Plain LaTeX gives you one command, \cite{key}, and it prints whatever the style dictates. That is not enough for author-year writing, where the citation is part of the sentence in one place and inside parentheses in another. natbib adds the distinction:

\usepackage[authoryear]{natbib}   % use [numbers] instead for [1]
\bibliographystyle{plainnat}      % must be a natbib-aware .bst

Command	Prints
\citet{vaswani2017attention}	Vaswani et al. (2017)
\citep{vaswani2017attention}	(Vaswani et al., 2017)
\citep[see][p. 5]{key}	(see Vaswani et al., 2017, p. 5)
\citeauthor{key} and \citeyear{key}	Vaswani et al. / 2017
\cite{key}	style-dependent — be explicit instead

The trap: in author-year mode, a style that is not natbib-aware (plain, abbrv, unsrt) raises Bibliography not compatible with author-year citations on the following run and drops the whole document back to numeric citations. natbib needs a .bst that emits author-year data — plainnat, abbrvnat, unsrtnat, or whichever natbib-aware style your venue ships.

Numeric citations compress if you ask them to: \usepackage[numbers,sort&compress]{natbib} turns \cite{a,b,c,d} into [1–4] rather than [1, 2, 3, 4].

Choosing a style

.bst	In-text	List order
plain	[1]	alphabetical by author
unsrt	[1]	order of first citation
abbrv	[1]	alphabetical, initials for given names
alpha	[Vas17] for a lone author, [VSP17] for the three-author entry above	alphabetical
ieeetr	[1]	order of first citation
plainnat	numeric or author-year, via natbib	alphabetical
abbrvnat	the same, with initials for given names	alphabetical

If the journal supplies a .bst, use it and ignore the table. If it only names a style in prose (“APA 7th”), biblatex with style=apa — the biblatex-apa package, which follows the 7th edition and requires Biber — is usually less painful than hunting for a BibTeX style that matches.

Route 2 — biblatex and Biber

\documentclass{article}
\usepackage[style=authoryear, backend=biber]{biblatex}
\addbibresource{refs.bib}   % with the extension, unlike \bibliography

\begin{document}

\textcite{vaswani2017attention} replaced recurrence with attention, and the
result has been reproduced widely \parencite{vaswani2017attention}.

\printbibliography

\end{document}

pdflatex main
biber    main    # not bibtex
pdflatex main
pdflatex main

Same shape, different second command. The citation commands rename cleanly: \textcite is natbib’s \citet, \parencite is \citep, and \footcite puts the citation in a footnote. Switching the whole document from numeric to author-year is one option — style=numeric becomes style=authoryear, then recompile. Under Route 1 that is a different .bst, and often a different package as well.

Two options you will want quickly: \printbibliography[title={References}, heading=bibintoc] renames the section and lists it in the table of contents, and \printbibliography[keyword=primary] prints a filtered subset. Filtered bibliographies have no BibTeX equivalent worth the effort.

Route 3 — no .bib file at all

For a five-reference course report, the whole apparatus is optional:

\begin{thebibliography}{9}

\bibitem{vaswani2017attention}
A. Vaswani, N. Shazeer, and N. Parmar.
\newblock Attention Is All You Need.
\newblock In {\em Advances in Neural Information Processing Systems}, 2017.

\end{thebibliography}

\cite{vaswani2017attention} works exactly as before and there is no second program to run — two LaTeX passes and you are done. In exchange you format every entry yourself, nothing sorts, and changing style means rewriting the list. It is worth knowing that this is precisely what BibTeX generates into main.bbl: routes 1 and 3 produce the same construct, one by program and one by hand.

Doing this without a local TeX install

The part that stays tedious in all three routes is the .bib file itself. Every entry is a record somebody typed: publisher pages export them with the venue in the wrong field, booktitle missing, names mangled. No style file repairs a wrong record.

Litlas works on that end. Its editor compiles LaTeX in the browser — a WebAssembly build of pdfTeX, so there is no local TeX installation to maintain — and citations come out of your saved library instead of being typed. Picking a paper from the library inserts \cite{key} at the cursor and merges that paper’s BibTeX entry into the document in the same action, so a citation and its entry cannot drift apart. The bibliography block does not have to exist first — the first citation creates one (the IEEE and ACM starters ship an empty one already). If you would rather have a real .bib, add one to the project and use \bibliography{refs}: the bundled engine runs classic BibTeX after each pass and repeats LaTeX (up to four passes) until references resolve, so the four-step chain above happens behind one Compile button. An existing .bib can be pasted or uploaded, and entries already present are skipped rather than duplicated.

The limitation to know before moving a manuscript there: the in-browser engine cannot run Biber. A Route 2 document compiles, but the bibliography does not resolve. The editor detects the combination and offers a one-click conversion to a thebibliography block that does compile — useful, but if your venue mandates biblatex, keep that document on a full local or server-side TeX. The free plan needs no card and covers this workflow, with caps (3 boards, 100 saved items, 5 searches a day); sharing a document by link is free, while inviting a co-author by email address is a paid feature.

Before you submit

1. Delete main.aux, main.bbl and main.blg, then run the full chain from clean. A stale .bbl hides problems until the deadline.
2. Search the output PDF for [?] and for the word undefined.
3. Read main.blg. Missing required fields are warnings there, not errors, so nothing stops you from submitting a reference with no year in it.
4. Confirm the style is the one the venue asked for, not the one that came with the template you copied.