# Bibliography

##### info

This documentation page describes the several components of using bibliographies one by one. However, you need them all before you can generate an output.

Additionally, in contrast to Overleaf, most installations are not configured to trigger biber (explained later) automatically. This article has not been yet completed to tell how to do this for VS Code. You will probably need some patience and endurance to figure that out yourself.

Some installation do not automatically trigger biber (explained later). Installations that do are Overleaf and VS Code when using latexmk. For other installations, ask me. For help outside a LaTeX course, send a mail to

Not available.

## Introduction#

Recall how we can refer to a figure like this

We see a penguin in Figure~\ref{fig:penguin}.
\begin{figure}[h]
\centering
\includegraphics[height=2cm]{assets/penguin.jpg}
\caption{A cute penguin. This a photo from the internet.}\label{fig:penguin}
\end{figure}


A similar system exists for referring to bibliography entries, but it is a bit more involved.

##### info

The tilde (~) yields a non-breaking space. It prevents breaking the text at that spot when wrapping the text onto the page. I.e., to avoid

Lorem ipsum dolor sit amet, consectetur adipiscing. We see a penguin in Figure
3.

__
-=(o '.
'.-.\
/|  \\
'|  ||
snd       _\_):,_

Figure 3: A cute penguin. The ASCII art is from
https://ascii.co.uk/art/penguins



## Cite command#

The \ref{} command is not used for citing sources. Instead we use a \cite{} command. When the bibliography style is set to numeric, this shows a number between square braces. The bibliography is in alphabetic order by default, and the numbers are therefore assigned in this order.

The necessary configurations to use the \cite{} command are presented in the next sections. See the following table to see which variations of the \cite{} command are available.

CodeOutput
\cite{mysource}[1]
\cite[21]{mysource}[1, p. 21]
\cite[21--30,8]{mysource}[1, pp. 21–30, 8]
\cite[See][21--30,8]{mysource}[See 1, pp. 21–30, 8]
\cite[See chapter 3 of][]{mysource}[See chapter 3 of 1]
\cite[See chapter 3 of]{mysource}[1, See chapter 3 of]
\cites{mysource}{othsource}[1, 7]

## The .bib-file#

The details of a source are given in a special format:

bibliography.bib
@book{babington,
author = {Peter Babington},
title = {Some work},
publisher = {Publisher},
year = 1993,
volume = 4,
series = 10,
edition = 3,
month = 7,
note = {An optional note},
isbn = {3257227892}
}


This entry is of type book, has key babington and contains fields necessary or optional for a source of type book. The key is what you use to cite the source:

CodeOutput
\cite{babington}[1]
\fullcite{babington}Peter Babington. Some work. 3de ed. Deel 4. 10. An optional note. The address: Publisher, jul 1993. isbn: 3257227892

(Language was set to Dutch when the \fullcite example was generated.)

You can add more entries to the file simply by appending them to the file. Beware that source keys should always be unique. The structure of bibliography.bib could for example look like

bibliography.bib
@article{babington,
...
}

@book{somebook,
...
}


## The .tex-file#

If you put the bibliography.bib file in the same directory as your main file (which I will call document.tex), then the main file looks like

document.tex
\documentclass[a4paper]{article}
\usepackage{biblatex}

\begin{document}
Lorem ipsum dolor sit amet \cite{babington}.
...
\printbibliography
\end{document}


The \printbibliography produces the bibliography, e.g.

## Biber and biblatex#

Biblatex is the LaTeX package which records which sources are cited and does the final typesetting. However, operations like reading the .bib-file and sorting entries is performed by a program, which should be shipped in your LaTeX installation. This program is called biber.

There is also an older system in use, for which the LaTeX package is called natbib and the backend program is called bibtex. Confusing names! The older system requires modifications to the .tex file, but the .bib file has the same format for both systems.

You can manually run biber by compiling your .tex file, then opening a terminal in the directory of your .tex file and running biber document, where your .tex file is assumed to be called document.tex. You can then recompile your document.tex and your cites should now be working.

Note that biber must be triggered each time you modified the .bib-file, or when you started or stopped citing a source. Else, the output might show outdated content. It is advisable to configure your editor to trigger biber automatically on compilation.

## Tweaking#

You can tweak the behavior of the bibliography in many ways. For example, you can change the citation style from numeric to APA, or change the sorting of the references. Refer to the BibLaTeX manual for details.

\usepackage[style=numeric,sorting=nty]{biblatex}
\usepackage[style=apa,sorting=none]{biblatex}


The References section is not automatically included in your table of contents. You may include it by adding

\addcontentsline{toc}{section}{References}


This sets the page number for the References section to be the page number at which that command executes. This might however be off, for example because the command is issued before the \printbibliography, and only the typesetting of the References header initiates the new page. At the time of writing, I do not have the time to destillate a general solution to this problem.

## Bib fields#

Refer to Wikibooks for overviews about which fields to include for your source.

## Multiple authors#

You separate multiple authors by the keyword and. LaTeX will properly do the comma's between them right. Providing the author in this format allows LaTeX to omit authors when desired. For example, consider

author = {A. Smith and B. Doe and E. Dropper and F. Foxtrot}


and use \textcite, like

CodeOutput
Lorem ipsum by \textcite{smith}.Lorem ipsum by A. Smith et al. [1].

Notice how it truncates the names to one name, and appends et al.. This is because the amount of names is greater than maxnames (by default 3), which causes truncation to an amount of minnames names (by default 1).

There are also the values maxbibnames and minbibnames. These are an override for showing names in the bibliography. For example, you might want to show more names here than in-text.

You can change these values by passing them as package options for biblatex:

\usepackage[maxnames=2,minnames=1,maxbibnames=4,minbibnames=2]{biblatex}