Cfrgtkky

I was using the APA format citation for my thesis, which I am writing in Overleaf, which uses an old version of biblatex-apa.

RequirePackage[style=apa, backend=biber]{biblatex}

My .bib file is:

@article

{Anderson1998,

     title={Diffuse-Interface Methods In Fluid Mechanics}, volume={30}, DOI={10.1146/annurev.fluid.30.1.139}, number={1}, journal={Annual Review of Fluid Mechanics}, author={Anderson, D. M. and Mcfadden, G. B. and Wheeler, A. A.}, year={1998}, pages={139–165}}



@article

{Penrose1990,

    title={Thermodynamically consistent models of phase-field type for the kinetic of phase transitions}, volume={43}, DOI={10.1016/0167-2789(90)90015-h}, number={1}, journal={Physica D: Nonlinear Phenomena}, author={Penrose, Oliver and Fife, Paul C.}, year={1990}, pages={44–62}}



@article

{NovickC1984,

    title={Nonlinear aspects of the Cahn-Hilliard equation}, volume={10}, DOI={10.1016/0167-2789(84)90180-5}, number={3}, journal={Physica D: Nonlinear Phenomena}, author={Novick-Cohen, Amy and Segel, Lee A.}, year={1984}, pages={277–298}} 



@book

{VanBrunt2010,

    place={New York}, title={The calculus of variations}, publisher={Springer}, author={Van Brunt, B.}, year={2010}}

I have been getting the entries for the .bib file from BibMe. The problem I encountered is that the output in my bibliography looks like this:

Anderson, D. M., Mcfadden, G. B., & Wheeler, A. A. (yearmonthday).
Diffuse-interface methods in fluid mechanics. Annual Review of Fluid
Mechanics , 30 (1), 139–165. doi:10.1146/annurev.fluid.30.1.139

Novick-Cohen, A. & Segel, L. A. (yearmonthday). Nonlinear aspects of
the cahn-hilliard equation. Physica D: Nonlinear Phenomena , 10 (3),
277–298. doi:10.1016/0167-2789(84)90180-5

Penrose, O. & Fife, P. C. (yearmonthday). Thermodynamically consistent
models of phase-field type for the kinetic of phase transitions.
Physica D: Nonlinear Phenomena , 43 (1), 44–62. doi:10.1016/0167-
2789(90)90015-h

Van Brunt, B. (yearmonthday). The calculus of variations . Springer.

I checked the APA format and you don't really need anything other than publication year for the citation.

Is there a way to modify the first command so that I only need the year instead of yearmonthday bibliography while keeping the APA format? (I can't get the months and days for some of the references here even if I tried, because they are not available online).

Overleaf runs an older version of biblatex-apa. In that version you must declare a language mapping to biblatex-apa's localisation files for each language you use. The mapping has the following form

DeclareLanguageMapping{<lang>}{<lang>-apa}

where <lang> is a babel language name.

If you load british with

documentclass[british]{article}

usepackage{babel}

...

you'll need

DeclareLanguageMapping{british}{british-apa}

For

usepackage[american,dutch]{babel}

you should load

DeclareLanguageMapping{american}{american-apa}

DeclareLanguageMapping{dutch}{dutch-apa}

A list of all language files can be found at https://github.com/plk/biblatex-apa/tree/master/tex/latex/biblatex-apa/lbx (though it could be that the older version on Overleaf does not support all of those yet). If you are using a language for which biblatex-apa does not have support, you will have to define certain things yourself on the fly.

documentclass[french,british,dutch]{article}

usepackage[T1]{fontenc}

usepackage[utf8]{inputenc}

usepackage{babel}

usepackage{csquotes}



usepackage[style=apa, backend=biber]{biblatex}



DeclareLanguageMapping{french}{french-apa}

DeclareLanguageMapping{british}{british-apa}

DeclareLanguageMapping{dutch}{dutch-apa}



addbibresource{biblatex-examples.bib}



begin{document}

cite{sigfridsson}

printbibliography

end{document}

With a current version of biblatex-apa (at least v7.5 from 2017-11-05, current is v7.7 from 2018-04-02) there should be no need for the DeclareLanguageMapping, because the mapping will be applied automatically. (That's also the reason the passage is gone from the biblatex-apa documentation.) The example from above would look like

documentclass[french,british,dutch]{article}

usepackage[T1]{fontenc}

usepackage[utf8]{inputenc}

usepackage{babel}

usepackage{csquotes}



usepackage[style=apa, backend=biber]{biblatex}



addbibresource{biblatex-examples.bib}



begin{document}

cite{sigfridsson}

printbibliography

end{document}