mnras.bst is the bibliography style file used for the latex2e Monthly Notices of the Royal Astronomical Society style file. See the journal's instructions for authors at OUP (Sect. 6.3), and the downloadable files at CTAN.

Previously this file was distributed by Blackwell Scientific.

Recent changes to the .bst file potentially require support from the mnras.cls class file.

• The .bst file generates references to DOIs, and to URIs mentioned in the .bib file, but using macros \doi and \url. The hyperref package defines the \url macro, but one can define suitable alternatives which typeset the URIs appropriately, even if they don't actually make the hyperlink. These macros are used only within the generated .bbl file. See below.

• The style file also generates references which implement MN's 'three authors' rule using a macro \mniiiauthor. These macros are used in citations (that is, via the \cite macro) and so outside the generated bibliography (in .bbl).

The file mnras-bst.sty contains the definitions required to support the newly-generated .bst output.

Currently, mnras.bst is configured so that (i) it incorporates the content of the mnras-bst.sty file into the generated .bbl file (see the function begin.bib, at the bottom), and (ii) the \mniiiauthor functionality is disabled, using the setting #0 threeauthorvar := in initialise.mnras. This means that the generated .bbl file is standalone, but doesn't support the MN 'three-authors' prescription.

Ideally, this file will be incorporated directly into the mnras.cls file, or at a pinch loaded as usual using the usual \usepackage{mnras-bst}. In this case, (i) the function begin.bib should be edited to remove the now-superfluous definitions; and (ii) the line #0 'threeauthorvar := in mnras.bst can be changed to #1 'threeauthorvar :=.

If hyperref is not used, then it is necessary to define the \href and \url macros as follows:

\def\href#1#2{#2}
\def\urlinner#1{#1\endgroup}
\def\url{\begingroup\def\do##1{\catcode`##1 12 }%
  \do\\\do\$\do\&\do\#\do\^\do\_\do\%\do\~ \ttfamily \urlinner}

(there is a more compact alternative at the top of mnras-bst.sty, which can be used within a class file).

This style file was originally written by John Sleath and Tim Jenness at the Mullard Radio Astronomy Observatory in the summer of 1995. It was derived from the astron.bst style file which itself was derived from the apalike.bst style file.

Norman Gray (http://nxg.me.uk and http://8ameter.com) provided the multi-author style fixes, and the additions to the style-file to support DOIs and the MN three-author requirement.

This style was originally known as mn2e.bst but has been renamed to mnras.bst to match the new naming convention for the recently upgraded mnras.cls.