# \setcitestyle error in Overleaf

I am trying to remove the comma between author and year when using \citet{} in an article class document on Overleaf. So, I have included the following code in the preamble:

\setcitestyle{notesep={; }, aysep={ }}


However, I get an 'Undefined control sequence' error. This previous post (Natbib setcitestyle causes "undefined control sequence error") indicates that the problem is caused by an outdated version of natbib that does not include the \setcitestyle function.

Is it possible to update natbib on Overleaf? However, I would expect that Overleaf would have the most up-to-date version of natbib...

%%%

Update with example code:

Renewing this biblatex command successfully removes comma.

\renewcommand*{\nameyeardelim}{\addspace}


Apparently there is a conflict between natbib and apalike or apacite. See here: http://latex-community.org/forum/viewtopic.php?t=23715

Can anyone confirm this? Any advice on best practice when using natbib and the authoryear style in biblatex?

\documentclass{book}

\usepackage[style=authoryear, citestyle=authoryear-comp, hyperref=true, backend=biber, natbib=true]{biblatex}

\usepackage{natbib}                         % gives error
\setcitestyle{notesep={; }, aysep={ }}          % gives error

%\renewcommand*{\nameyeardelim}{\addspace} % removes comma, no error

\usepackage{filecontents}
\begin{filecontents}{test.bib}
@article{kerth_information_2003,
title = {Information transfer about roosts in female {Bechstein}'s bats: an experimental field study},
volume = {270},
journal = {Proceedings of the Royal Society of London. Series B: Biological Sciences},
author = {Kerth, Gerald and Reckardt, Karsten},
year = {2003},
pages = {511--515}
}
\end{filecontents}

\begin{document}
A thing happen once, the thing was seen by \citet{kerth_information_2003}.
\end{document}

• You cannot really update packages in Overleaf. You might be able to upload all needed files into your project, but that gets cumbersome quite soon and might cause other trouble down the way (especially due to package dependency). Note thought that the answer you linked to mentions packages from 2010, I'm quite sure Overleaf is more up to date than that. Please shown us an MWE of what you are trying to achieve. You might want to confirm you are really loading natbib. BTW: your question is tagged biblatex do you use that package? – moewe Jan 29 '17 at 17:19
• I can confirm \usepackage{natbib}\setcitestyle{notesep={; }, aysep={ }} works fine on Overleaf. Perhaps check that natbib was really indeed loaded? – LianTze Lim Jan 31 '17 at 1:53
• @moewe Thanks for the advice, this is my first post! I have added some example code that produces the error. – John R Giles Feb 1 '17 at 3:58
• @LianTzeLim The problem might be a conflict between natbib and apalike. Renewing this biblatex command worked \renewcommand*{\nameyeardelim}{\addspace} – John R Giles Feb 1 '17 at 4:00

You cannot use biblatex and natbib. You can get natbib support within biblatex, but you cannot use natbib. This is independent of the Biblatex style you select. It matters not whether it is apalike or something else.
Biblatex uses its own interface for formatting the citations and bibliography. It does not use BibTeX .bst files, which are at the core of natbib's approach. No BibTeX styles are compatible with Biblatex. They are quite different ways of managing the references and bibliography.
If you want to use Biblatex, you need to stick to Biblatex's interface. If you want natbib, drop biblatex.
That is, the best practice when using natbib and Biblatex, regardless of style, is