How to order citations by appearance using BibTeX?

Question

By default (using the plain style) BibTeX orders citations alphabetically.

How to order the citations by order of appearance in the document?

Answer 1

There are three good answers to this question.

• Use the unsrt bibliography style, if you're happy with its formatting otherwise
• Use the makebst (link) tool to design your own bibliography style

And my personal recommendation:

• Use the biblatex package (link). It's the most complete and flexible bibliography tool in the LaTeX world.

Using biblatex, you'd write something like

\documentclass[12pt]{article}
\usepackage[sorting=none]{biblatex}
\bibliography{journals,phd-references} % Where journals.bib and phd-references.bib are BibTeX databases
\begin{document}
\cite{robertson2007}
\cite{earnshaw1842}
\printbibliography
\end{document}