[Tex/LaTex] (labelyearlabelmonthlabelday) in biblatex-apa bibliography

apa-stylebiblatex

I'm having trouble using biblatex-apa to create a bibliography. When I run my project through latexmk, I get a reference section that looks like this:

Chan, K., Van Zwieten, L., Meszaros, I., Downie, A., & Joseph, S. (labelyearlabelmonth- labelday). Agronomic values of greenwaste biochar as a soil amendment. Soil Research, 45(8), 629–634.

Rondon, M. A., Lehmann, J., Ram ́ırez, J., & Hurtado, M. (labelyearlabelmonthlabelday). Biological nitrogen fixation by common beans (phaseolus vulgaris l.) increases with bio-char additions. Biology and Fertility of Soils, 43 (6), 699–708.

I took a look at this answer to a similar problem, but none of the suggestions worked for me.

My bibliography file entries look like this:

@article{rondon2007biological,
    Author = {Rondon, Marco A and Lehmann, Johannes and Ram{\'\i}rez, Juan and Hurtado, Maria},
    Date-Added = {2014-01-05 23:51:41 +0000},
    Date-Modified = {2014-01-05 23:51:41 +0000},
    Journal = {Biology and Fertility of Soils},
    Number = {6},
    Pages = {699--708},
    Publisher = {Springer},
    Title = {Biological nitrogen fixation by common beans (Phaseolus vulgaris L.) increases with bio-char additions},
    Volume = {43},
    Year = {2007},
    }

@article{chan2008agronomic,
    Author = {Chan, KY and Van Zwieten, L and Meszaros, I and Downie, A and Joseph, S},
    Journal = {Soil Research},
    Number = {8},
    Pages = {629--634},
    Publisher = {CSIRO},
    Title = {Agronomic values of greenwaste biochar as a soil amendment},
    Volume = {45},
    Year = {2008},
}

My .tex file looks like this (with most of the content removed for conciseness):

\documentclass[12pt,a4paper]{article}
\usepackage{fullpage,graphicx, url}
\usepackage[american]{babel}
\usepackage{csquotes}
\usepackage[backend=biber,style=apa]{biblatex}
\usepackage[version=3]{mhchem}
\DeclareLanguageMapping{british}{british-apa}
\addbibresource{biochar.bib}
\date{}
\begin{document}
    \parencite{chan2008agronomic}.
    \parencite{rondon2007biological}
    \printbibliography 
\end{document}

Any help with this problem would be greatly appreciated. I'm pretty new to bib latex, so I'll admit that I could very well be doing something extremely stupid. I'm using TeXLive 2013 on Mac OS X Mavericks, if that makes any difference.

Best Answer

The file contains both

\usepackage[american]{babel}

and

\DeclareLanguageMapping{british}{british-apa}

One has to use one of the two options above, not both.