Biblatex APA – Suppressing Month in Biblatex-APA Style

apa-stylebiberbiblatex

Please consider the following MWE

\RequirePackage{filecontents}

\begin{filecontents*}{mybib.bib}
@article{test1,
    title = {Structural holes and good ideas},
    volume = {110},
    issn = {0002-9602, 1537-5390},
    doi = {10.1086/421787},
    number = {2},
    urldate = {2012-10-04},
    journal = {American {Journal} of {Sociology}},
    author = {Burt, Ronald S.},
    month = sep,
    year = {2004},
    pages = {349--399},
}
@book{test2,
    address = {New {York}, {NY}},
    edition = {1st ed.},
    title = {Understanding media: {The} extensions of man},
    lccn = {P90 .M26},
    publisher = {McGraw-{Hill}},
    author = {{McLuhan}, Marshall},
    year = {1964}
}
\end{filecontents*}

\documentclass[a4paper]{article}


% Set the values for the bibliography
\usepackage[
    style=apa,
    backend=biber,
    isbn=false,
    url=false,
    doi=false,
    eprint=false,
    hyperref=true,
    backref=false,
    firstinits=false
]{biblatex}

% Recommended by biblatex
\usepackage[utf8]{inputenc}
\usepackage{csquotes}
\usepackage{xpatch}

% Remove series & month
\AtEveryBibitem{
  \clearfield{month}
  \clearfield{edition}
}

% Set language
\usepackage[british]{babel}
\DeclareLanguageMapping{british}{british-apa}

\addbibresource{mybib.bib}

\begin{document}

\cite{test1} \cite{test2}

\printbibliography
\end{document}

I don't get why the option \clearfield{edition}successfully suppress the edition from the second reference, while the option \clearfield{month}doesn't succeed in getting rid of the month:

Burt, R. S. (2004, September)

instead of what I would like to see:

Burt, R. S. (2004)

Best Answer

In author-year styles (such as biblatex-apa), the month field is used in composing the Labelmonth (kind of meta-) field. You can clear it in the bibliography by issuing a:

\AtEveryBibitem{
  \clearfield{labelmonth}
}

Here's a simplified version of your MWE:

\RequirePackage{filecontents}
\begin{filecontents*}{\jobname.bib}
@article{test1,
    title = {Structural holes and good ideas},
    volume = {110},
    issn = {0002-9602, 1537-5390},
    doi = {10.1086/421787},
    number = {2},
    urldate = {2012-10-04},
    journal = {American {Journal} of {Sociology}},
    author = {Burt, Ronald S.},
    month = sep,
    year = {2004},
    pages = {349--399},
}
@book{test2,
    address = {New {York}, {NY}},
    edition = {1st ed.},
    title = {Understanding media: {The} extensions of man},
    lccn = {P90 .M26},
    publisher = {McGraw-{Hill}},
    author = {{McLuhan}, Marshall},
    year = {1964}
}
\end{filecontents*}
\documentclass[a4paper]{article}
\usepackage[style=apa,backend=biber]{biblatex}
\AtEveryBibitem{
  \clearfield{labelmonth}
}
\usepackage[british]{babel}
\DeclareLanguageMapping{british}{british-apa}
\addbibresource{\jobname.bib}
\begin{document}
\thispagestyle{empty}
\cite{test1} \cite{test2}
\printbibliography
\end{document}

mwe