# APA cite multiple authors -- why switch order will affect the effect?

I want to cite two paper, which both more than three authors in APA format. As far as I know, when number of the author is more than three, no matter if it is the first time, only the first author will be display. I am using the overleaf platform, and wondering why switch the citation order will change the format.

here is the how I cite the paper,

such as A and B
\citep{Petkov2008,Petkov2009} \citep{Petkov2009,Petkov2008}


here is how the compiled file show. such as A and B (Petkov et al., 2008; Petkov, Logothetis, & Obleser, 2009) (Petkov et al.,2008, 2009

here is how those two paper looks in the reference.bib

@article{Petkov2008,
author = {Petkov, Christopher and Kayser, Christoph and Steudel, Thomas and Whittingstall, Kevin and Augath, Mark and Logothetis, Nikos},
year = {2008},
month = {04},
pages = {367-74},
title = {A voice region in the monkey brain},
volume = {11},
journal = {Nature neuroscience},
doi = {10.1038/nn2043}
}

@article{Petkov2009,
author = {Petkov, Christopher and Logothetis, Nikos and Obleser, Jonas},
year = {2009},
month = {07},
pages = {419-29},
title = {Where Are the Human Speech and Voice Regions, and Do Other Animals Have Anything Like Them?},
volume = {15},
journal = {The Neuroscientist : a review journal bringing neurobiology, neurology and psychiatry},
doi = {10.1177/1073858408326430}
}


thank you all for the time and help:)))

• Welcome to TeX.SE.
– Mico
Mar 16 at 11:46
• I'm not sure, whether I get your question correctly, but for me, everything seems to be okay: the 2009 paper has three authors, all are listed, and the 2008 paper has more than three authors, only the first is listed. What exactly is your problem? Mar 16 at 11:57
• There is a difference between 6th-edition APA style and 7th-edition APA style in the expected behaviour here: For 3 to 6 (I think, maybe its 3 to 5 or 3 to 7) authors 6th-edition APA style wants all authors on first cite and first author + "et al." on subsequent citations of the same work. 7th-edition APA style has the same citation label in all citations. apacite implements 6th-ed. APA style. In the LaTeX world 7th-ed. APA style is currently only available with biblatex-apa. Mar 16 at 16:55
• @moewe that's what confused me. thank you for the explanation. Mar 16 at 21:56

If I interpret the (somewhat fragementary) information you've provided correctly, you're using the apacite citation management system -- likely with the option natbibapa -- and the apacite bibliography style. Do be advised that apacite implements the formatting requirements of the 6th edition of the APA manual.

If your document needs to adhere to the formatting requirements of the current, 7th edition of the manual, your only viable choice at present is to make the switch to biblatex/biber and employ to the apa style. (There's also the apa6 style which, I'm sure you can guess, implements the formatting requirements of the 6th ed.)

\documentclass{article}
\begin{filecontents}[overwrite]{mybib.bib}
@article{Petkov2008,
author  = {Petkov, Christopher and Kayser, Christoph and Steudel, Thomas
and Whittingstall, Kevin and Augath, Mark and Logothetis, Nikos},
year    = {2008},
month   = {04},
pages   = {367--74},
title   = {A voice region in the monkey brain},
volume  = {11},
journal = {Nature Neuroscience},
doi     = {10.1038/nn2043}
}

@article{Petkov2009,
author = {Petkov, Christopher and Logothetis, Nikos and Obleser, Jonas},
year   = {2009},
month  = {07},
pages  = {419--29},
title  = {Where Are the Human Speech and Voice Regions, and
Do Other Animals Have Anything Like Them?},
volume = {15},
journa = {The Neuroscientist: A review journal bringing neurobiology,
neurology and psychiatry},
doi    = {10.1177/1073858408326430}
}
\end{filecontents}

\usepackage[style=apa,natbib]{biblatex}

\usepackage{xurl}

\begin{document}
\citep{Petkov2008,Petkov2009}

\citet{Petkov2008,Petkov2009}
\printbibliography
\end{document}

• sorry for the missing information. your interpret is totally correct and your pic is exactly what I want. i stored the header.tex , main.tex and references.bib seperately, not sure where I should do the overwrite part. I tried to revise based on your script by adding \usepackage[style=apa,natbib]{biblatex} \addbibresource{References.bib} after \usepackage[natbibapa]{apacite} % citation style but then all the reference in paper become ??? Mar 16 at 22:27
• @user226555 - The apacite and biblatex packages are mutually incompatible. Use one or the other, but not both.
– Mico
Mar 16 at 23:22
• thank you, it helps a lot, so far I replace apacite with biblatex, \citet to \textcitea and \citep to \parencite. but I still dont get what is the file content for? now I store the references in References.bib, is it okay? Mar 17 at 15:44
• @user226555 - If you load the biblatex package as \usepackage[style=apa,natbib]{biblatex} (as in the answer above), you can keep using \citet and \citep. (Of course, you don't have to use the natbib option; it's meant mainly as a convenience.) The filecontents environment is used in my answer purely as a convenience to create the sample file mybib.bib "on the fly". Naturally, if your real references are stored in a file called References.bib, you should specify \addbibresource{References.bib}, not \addbibresource{mybib.bib}.
– Mico
Mar 17 at 16:06