How to edit bibtex entry for a bimonthly IEEE journal?

Question

IEEE bibtex style uses the following entry for a typical journal paper:

@article{foobar,
  author  = "A. Boo, C. Foo",
  title   = "Paper Title of His",
  journal = IEEE_J_IA,
  volume  = "40",
  month   = jan,
  year    = "2012",
  pages   = "1-11"
}

The journal "IEEE Transaction of Industry Applications" is bimonthly, so IEEE usually says "January-February 2012" (example). How do I edit the month field? The following issues error

Warning--string name "jan/feb" is undefined

at compile time due to

month = jan/feb

Answer 1

bibtex allows you to concatenate strings using #. Thus for a bimonthly issue of journal you can use

month = jan # "/" # feb

See Section 2 of the bibtex manual (texdoc bibtex)