# problem with biblatex-chem bundle, babel, and inbook entry

I'm writing my thesis in French, and thus use the package babel. I have chosen the "chem-angew" bibliography style, and all is good so far, except for citations of chapters in books.

Here is my bib entry for that peculiar reference:

@InBook{Lumb1978,
author = {G.F.Imbusch},
editor = {M.D.Lumb},
booktitle = {Luminescence Spectroscopy},
chapter = {1},
year = {1978},
pages = {27}
}


And here is what comes out :

G.F.Imbusch dans, Luminescence Spectroscopy, (éd. : M.D.Lumb), Academic Press, 1978, chap. 1, p. 27 (cf. p. 7).

It's all good, since "dans" means "in" in French. However, there should not be a comma after that "dans".

How comes this is there and how do I remove it ?

For the @inbook entry type, you seem to have stumbled upon a small bug in biblatex and the chem-angew style: A \newunitpunct (by default a comma and a space) is printed after the bookauthor field even if the content of this field is identical to author (or, as in your case, empty) -- note that biblatex doesn't print the same name twice. The superfluous punctuation can be removed by patching the inbook bibliography driver (note: \setunit* prints its argument only if the last command did actually print anything):

\documentclass{article}

\usepackage[french]{babel}

\usepackage[style=chem-angew]{biblatex}

\usepackage{xpatch}

\xpatchbibdriver{inbook}{%
\usebibmacro{in:}%
\usebibmacro{bybookauthor}%
\newunit\newblock
}{%
\usebibmacro{in:}%
\usebibmacro{bybookauthor}%
\setunit*{\newunitpunct}\newblock
}{}{}

\usepackage{filecontents}

\begin{filecontents}{\jobname.bib}
@inbook{Lumb1978,
author = {G.F.Imbusch},
editor = {M.D.Lumb},
booktitle = {Luminescence Spectroscopy},
chapter = {1},
year = {1978},
pages = {27},
}
\end{filecontents}

\nocite{*}

\begin{document}

\printbibliography

\end{document}


As you didn't specify a bookauthor, maybe the @incollection type is more appropriate for your entry (check section 2.2.1 of the biblatex manual for details) -- and @incollection doesn't suffer from the above bug.

\documentclass{article}

\usepackage[french]{babel}

\usepackage[style=chem-angew]{biblatex}

\usepackage{filecontents}

\begin{filecontents}{\jobname.bib}
@incollection{Lumb1978,
author = {G.F.Imbusch},
editor = {M.D.Lumb},
booktitle = {Luminescence Spectroscopy},
chapter = {1},
year = {1978},
pages = {27},
}
\end{filecontents}