# “Undefined Control Sequence”-Error when using Biblatex with apa style

Today I started to try biblatex for the first time in my apa6.cls document:

\documentclass[ngerman,man,12pt,a4paper,noextraspace,donotrepeattitle]{apa6}
\usepackage[latin1]{inputenc}
\usepackage[english,ngerman]{babel}
\usepackage[T1]{fontenc}
\usepackage{lmodern}
\usepackage{etoolbox}

\usepackage{csquotes}
\usepackage[style=apa,sortcites=true,sorting=nyt,backend=biber]{biblatex}
\DeclareLanguageMapping{ngerman}{ngerman-apa}

\begin{document}

\cite{vonDavier2011}

\printbibliography

\end{document}


I just copied the content of the .bib file from the bibliography.bib of the apa6.cls example file for some testing so the .bib content is alright.

This works as long as I load biblatex only with \usepackage[backend=biber]{biblatex}. But when I additionally specify apa citation style like in the example above, I get the Error

right after the \printbibliography line.

I have to mention that I am not an advanced latex or even biblatex user. F. e. I just changed the output profile from bibtex to biber and don't know what is meant with "biber %" I read about in other topics. Should I include that anywhere?

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The error lies in declaring the ngerman option in the \documentclass line.

Here's what happens. When babel is loaded, it is passed all the global options, so ngerman; then it examines the local options, english and ngerman; since the latter has already been loaded, it has no effect and the main language becomes English.

You can check this by adding \languagename after \begin{document}, which will print “english”.

Solution: don't use ngerman in \documentclass or use both. If you have babel version 3.9, you can solve also by issuing

\usepackage[english, main=ngerman]{babel}


and, in this case, the ngerman option in \documentclass will do no damage.

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Ok, I removed it in the document options and that worked. The language command still says "ngerman" is the document language, which is good. Nevertheless I still get a "package biblatex warning macro 'name:apa:first-last' undefined" Warning... do you might have any idea on that also? –  entne Sep 3 '13 at 18:42
@entne I get no warning, sorry. –  egreg Sep 3 '13 at 19:55