# Unexpected behavior with biblatex-chicago and references with more than three authors

I have an unexpected behavior using biblatex-chicago and references with more than three authors.

An MWE of my TeX:

\documentclass{article}
\usepackage[backend=biber,authordate,uniquelist]{biblatex-chicago}
\bibliography{ref}

\begin{document}
\autocite{batty2007iq}

\autocite{batty2007premorbid}

\autocite{batty2009iq_early}

\autocite{batty2009iq_socio}

\printbibliography
\end{document}


and my bib:

  @article{batty2007iq,
title={IQ in early adulthood and later cancer risk: cohort study of one million Swedish men},
author={Batty, G. David and Wennerstad, Karin Modig and Smith, George Davey and Gunnell, David and Deary, Ian J. and Tynelius, Per and Rasmussen, Finn},
journal={Annals of Oncology},
volume={18},
number={1},
pages={21--28},
year={2007},
publisher={European Society for Medical Oncology}
}

@article{batty2007premorbid,
title={Premorbid (early life) IQ and Later Mortality Risk: Systematic Review},
author={Batty, G. David and Deary, Ian J. and Gottfredson, Linda S.},
journal={Annals of Epidemiology},
volume={17},
number={4},
pages={278--288},
year={2007},
publisher={Elsevier}
}

@article{batty2009iq_early,
title={IQ in Early Adulthood and Mortality By Middle Age: Cohort Study of 1 Million Swedish Men},
author={Batty, G. David and Wennerstad, Karin Modig and Smith, George Davey and Gunnell, David and Deary, Ian J. and Tynelius, Per and Rasmussen, Finn},
journal={Epidemiology},
volume={20},
number={1},
pages={100--109},
year={2009},
publisher={LWW}
}

@article{batty2009iq_socio,
title={IQ in Early Adulthood, Socioeconomic Position, and Unintentional Injury Mortality by Middle Age: A Cohort Study of More Than 1 Million Swedish Men},
author={Batty, G. David and Gale, Catharine R. and Tynelius, Per and Deary, Ian J. and Rasmussen, Finn},
journal={American Journal of Epidemiology},
volume={169},
number={5},
pages={606--615},
year={2009},
publisher={Oxford University Press}
}


Above code results in:

which is not what I want. However, if I comment \autocite{batty2007iq} or \autocite{batty2009iq_early}, I get the result I want (except the commented reference, obviously), e.g:

I do not understand why my code results in "Batty et al. 2007" and "Batty et al. 2009" and not "Batty, Wennerstad, et al. 2007" and "Batty, Wennerstad, et al. 2009". For a reader it is hard to distinguish the exact reference.

To be clear, what I want is this:

(Batty, Deary, and Gottfredson 2007)

(Batty, Gale, et al. 2009)

Is that possible?

Edit: I forgot one thing. I only want two names in the cite if the reference otherwise would be unclear. I cite many "more than three authors" papers, but for those papers (Lastname et al. Year) is perfectly fine.

In a way I would have actually expected the output you want from the disambiguation feature (especially after reading §4.11.4.2 Lists of Names (uniquelist), p. 237-238 of the biblatex documentation, there we always get unambiguous et als).

This issue has been addressed by the Biber developer. In version 2.7 the output should be as expected. See biblatex issue #336, as well as biblatex issue #487, which was sparked by Setting uniquelist=true should print second author in all corresponding lists of names

For pre-2.7 versions of Biber. We need to find a work-around. Enter a bit of cheating: mincitenames can be set on a per-entry basis, so I added it to batty2007iq and batty2009iq_early via the options field.

\documentclass{article}
\usepackage[backend=biber,authordate,uniquelist=true]{biblatex-chicago}

\usepackage{filecontents}
\begin{filecontents}{\jobname.bib}
@article{batty2007iq,
title={IQ in early adulthood and later cancer risk: cohort study of one million Swedish men},
author={Batty, G. David and Wennerstad, Karin Modig and Smith, George Davey and Gunnell, David and Deary, Ian J. and Tynelius, Per and Rasmussen, Finn},
journal={Annals of Oncology},
volume={18},
number={1},
pages={21--28},
year={2001},
publisher={European Society for Medical Oncology},
options = {mincitenames=2},
}

@article{batty2007premorbid,
title={Premorbid (early life) IQ and Later Mortality Risk: Systematic Review},
author={Batty, G. David and Deary, Ian J. and Gottfredson, Linda S.},
journal={Annals of Epidemiology},
volume={17},
number={4},
pages={278--288},
year={2002},
publisher={Elsevier},
}

@article{batty2009iq_early,
title={IQ in Early Adulthood and Mortality By Middle Age: Cohort Study of 1 Million Swedish Men},
author={Batty, G. David and Wennerstad, Karin Modig and Smith, George Davey and Gunnell, David and Deary, Ian J. and Tynelius, Per and Rasmussen, Finn},
journal={Epidemiology},
volume={20},
number={1},
pages={100--109},
year={2003},
publisher={LWW},
options = {mincitenames=2},
}

@article{batty2009iq_socio,
title={IQ in Early Adulthood, Socioeconomic Position, and Unintentional Injury Mortality by Middle Age: A Cohort Study of More Than 1 Million Swedish Men},
author={Batty, G. David and Gale, Catharine R. and Tynelius, Per and Deary, Ian J. and Rasmussen, Finn},
journal={American Journal of Epidemiology},
volume={169},
number={5},
pages={606--615},
year={2004},
publisher={Oxford University Press},
}
\end{filecontents}

\begin{document}
\autocite{batty2007iq}

\autocite{batty2007premorbid}

\autocite{batty2009iq_early}

\autocite{batty2009iq_socio}

\printbibliography
\end{document}


• I'm really not sure how these disambiguation features are supposed to work and certainly very hesitant to call this a bug, but maybe some of the biblatex maintainers has a look at this and can give some insight into this. Sep 11 '15 at 16:45
• Thanks! Though not the ideal solution, this works. (I am not sure if I am supposed to mark this answer as a solution as it is not "permanent".) Sep 12 '15 at 7:02
• @MattiasÖhman In what way is it not permanent? (It is ad-hoc, I will give you that.) You can accept the answer if you are content with it and if someone comes along with something better, accept the other, better answer. Sep 12 '15 at 7:27
• Ok, sure, ad hoc. :-) It requires one to update the bib on a per-entry basis in a way that can become rather cumbersome if you often add/remove references, which really should not be necessary, as I see it. What I want is, I guess, what a journal would require. Sep 12 '15 at 7:44
• @MattiasÖhman Yep. I was counting on you not having so many entries in your database that require this treatment. As I said, name disambiguation is quite complicated and biblatex does an awesome job at it. In that case the output might not be what you expect, but then just ask the maintainers (at the github bug tracker) if they can implement your wish. Sep 12 '15 at 7:50

Use the optional arguments for names:

\usepackage[authordate,uniquelist,maxnames=3,minnames=2]{biblatex-chicago}

\usepackage[authordate,uniquelist,maxcitenames=3,mincitenames=2]{biblatex-chicago}