TeX - LaTeX Stack Exchange is a question and answer site for users of TeX, LaTeX, ConTeXt, and related typesetting systems. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

When citing a page, the Biblatex manual puts a tilde between "p."/"page" and the number:


Why? I actually have never really googled for this and now that I have, I am unable to find any good results or think of one.

I recall that I used

\footcite[Cp.][p. 23]{Smith-2013}

a couple of times and I didn't have any problems with the space disappearing or anything. Then I converted back to the tilde method just for the sake of it but did not inquire about it.

share|improve this question
~ is a non-breakable space. – Gonzalo Medina Mar 22 '14 at 15:07
@GonzaloMedina I am aware of that and this was not my question. – henry Mar 22 '14 at 15:07
Then what is your question? – Gonzalo Medina Mar 22 '14 at 15:09
If this question is really about biblatex, do not write \footcite[Cp.][p.~23]{Smith-2013} but \footcite[Cp.][23]{Smith-2013}. If the postnote only contains a number (actually, more specifically, something biblatex recognises as page range), it adds the "page"/"p" prefix and an appropriate space itself. – moewe Mar 22 '14 at 15:14
biblatex automatically adds a \ppspace between the page prefix ("p."/"page") and the actual page number. \ppspace defaults to \addnbspace, a non-breaking space. (All this can be found in biblatex2.sty.) – moewe Mar 22 '14 at 15:20
up vote 5 down vote accepted

~ is a non-breakable space so no line break will separate the "p." and the number. Not using it might result (if the string "p. #" happens to be close to a lind end) in the string "p." and the number on different lines (even on different pages if "p." is close to a page break) which is not correct.

This is a case of a general rule: when an object is mentioned together with a number (for example, when one cross-references a figure in the form "Figure 5 on page 234"), the object and its associated number must not be separated by a line break. Thus, one has to introduce non-breakable spaces at the proper locations: Figure~\ref{fig:image} on page~\pageref{fig:image}.

share|improve this answer
Really, that's it? In the case there was a line break in the footnote, I assume the majority of times the page reference isn't broken. As in, never. I never had that problem. But then... my thought was probably based on pointless egotistical thinking. – henry Mar 22 '14 at 15:11
@henry The fact that it has not occurred to you up to this moment doesn't rules out the possibility of it happening to someone at some time :) – Gonzalo Medina Mar 22 '14 at 15:12
Very true... :) – henry Mar 22 '14 at 15:21
@henry The problem is not so much if you use this in a footnote (\footcite), but if you use \cite, \parencite or \textcite, "p. #" might well hit the end of a line. – moewe Mar 22 '14 at 15:27
My first comment here seems out of place now. When I posted it there was just the first sentence written in the reply. @moewe that is a good point. – henry Mar 23 '14 at 7:28

Two things: line breaks and spacing. Without the tilde, TeX an break between 'p.' (or page) and '23' in the example. It's normally considered 'bad style' to have a break here or in any case where you have 'Thing X'-type links. In the specific case of p., as you are using a full stop (period) preceded by a lower case letter, TeX will treat this as an end-of-sentence and may insert extra space (depending on whether \frenchspacing is active). To prevent this you certainly need p.\ 23 even if you want to allow a line break (not a good idea).

Note that depending on the exact nature of your input you may not notice the first issue (of not occurring at a break) or the second (if \frenchspacing is set).

share|improve this answer
Interesting. Also, I wasn't aware that it was 'bad style'. – henry Mar 22 '14 at 15:20

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.