@string{jams    = {J.~Amer. Math. Soc.}}

@article{bertram,
    author       = {Bertram, Aaron and Wentworth, Richard},
    title        = {Gromov invariants for holomorphic maps on {Riemann} surfaces},
    journaltitle = jams,
    date         = 1996,
    volume       = 9,
    number       = 2,
    pages        = {529-571},
    langid       = {english},
    langidopts   = {variant=american},
    shorttitle   = {Gromov invariants},
    annotation   = {An \texttt{article} entry with a \texttt{volume} and a
                    \texttt{number} field},
}