-#LyX 2.0.0svn created this file. For more info see http://www.lyx.org/
-\lyxformat 404
+#LyX 2.0.0beta2 created this file. For more info see http://www.lyx.org/
+\lyxformat 410
\begin_document
\begin_header
\textclass scrbook
\font_sans default
\font_typewriter default
\font_default_family default
-\use_xetex false
+\use_non_tex_fonts false
\font_sc false
\font_osf false
\font_sf_scale 100
\end_inset
Spécial
+\family default
+\lang english
+LaTeX font support
\end_layout
\begin_layout Itemize
typographiques.
\end_layout
+\begin_layout Subsection
+
+\lang english
+LaTeX font support
+\begin_inset CommandInset label
+LatexCommand label
+name "sub:LaTeX-font-support"
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+
+\lang english
+Traditionally, LaTeX uses its own fonts.
+ That is to say, you cannot directly access the fonts installed on your
+ operating system, but you have to use specific fonts provided by your LaTeX
+ distribution.
+ The reason is that LaTeX needs some extra information about the fonts,
+ which have to be provided by additional files and packages.
+ The downside of this is that your font choice is somewhat limited, compared
+ to usual word processors.
+ On the other hand this comes with the advantage that the provided fonts
+ are generally of very good quality, and that LaTeX files are very portable
+ across different machines.
+ Also, the range of fonts supported by traditional LaTeX was increased a
+ lot meanwhile so that you can find packages for many free and commercial
+ fonts.
+ In LyX, only a subset of these are directly selectable via the user interface
+ (see section
+\begin_inset space ~
+\end_inset
+
+
+\begin_inset CommandInset ref
+LatexCommand ref
+reference "sub:Document-Polices"
+
+\end_inset
+
+ for details).
+ However, all others are available if you enter the respective LaTeX code
+ in the document preamble (please refer to the documentation of your desired
+ font).
+\end_layout
+
+\begin_layout Standard
+
+\lang english
+Furthermore, recent developments brought some new LaTeX engines that are
+ also able to directly access fonts that are installed for your operating
+ system (OS), namely XeTeX and LuaTeX.
+ Both engines are now supported by LyX.
+ By using them, you can use theoretically any OpenType or TrueType font
+ that is installed on your system (note though, that ).
+ The next section describes how to use these OS fonts.
+\end_layout
+
+\begin_layout Standard
+
+\lang english
+\begin_inset Note Greyedout
+status open
+
+\begin_layout Plain Layout
+
+\series bold
+\lang english
+Note:
+\series default
+ In practice, some fonts might fail due to bad metrics and other font deficienci
+es; so you might have to experiment.
+\end_layout
+
+\end_inset
+
+
+\end_layout
+
+\begin_layout Standard
+
+\lang english
+\begin_inset Note Greyedout
+status open
+
+\begin_layout Plain Layout
+
+\series bold
+\lang english
+Note:
+\series default
+ XeTeX and especially LuaTeX, are still rather new and thus not as mature
+ as traditional LaTeX or PDFLaTeX.
+\end_layout
+
+\end_inset
+
+
+\end_layout
+
\begin_layout Subsection
Les Polices du Document et les Tailles de Polices
\begin_inset CommandInset label
\end_inset
.
- Vous pouvez y définir quelle police utiliser pour les trois familles de
- caractères: Romain,
+
+\lang english
+In the
\family sans
-Sans
+Fonts
+\family default
+ section of the dialog, you can specify which font should be used for the
+ three different font shapes — roman (serif),
+\family sans
+sans
\begin_inset space ~
\end_inset
-Serif
+serif
\family default
-, et
+ and
\family typewriter
-Chasse
-\begin_inset space ~
+typewriter
+\family default
+ (monospaced) — you can specify the base font size and scaling factors for
+ (some) sans serif and typewriter fonts if this is necessary to fit with
+ the roman font.
+\end_layout
+
+\begin_layout Standard
+
+\lang english
+If you select
+\family sans
+Use non-T
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+{}
+\end_layout
+
+\end_inset
+
+eX fonts
+\family default
+, you will have access to the fonts installed on your operating system.
+ This requires that you use
+\family sans
+PDF (XeT
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+{}
+\end_layout
+
+\end_inset
+
+eX)
+\family default
+,
+\family sans
+PDF (LuaT
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+{}
+\end_layout
+
+\end_inset
+
+eX)
+\family default
+ or
+\family sans
+DVI (LuaT
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+{}
+\end_layout
+
\end_inset
-Fixe
+eX)
\family default
- et leurs tailles.
+ as output format, i.
+\begin_inset space \thinspace{}
+\end_inset
+
+e.
+\begin_inset space ~
+\end_inset
+
+you will have to have either XeTeX or LuaTeX installed (see section
+\begin_inset space ~
+\end_inset
+
+
+\begin_inset CommandInset ref
+LatexCommand ref
+reference "sub:LaTeX-font-support"
+
+\end_inset
+
+).
+ You will then not have access to TeX's own fonts (the selection described
+ below).
+ Note that LyX lists all available fonts in either of the three lists (roman,
+ sans
+\begin_inset space ~
+\end_inset
+
+serif, and typewriter), since LyX cannot determine the family.
+ Also note that the output might fail with some of the listed fonts, due
+ to the encoding of the fonts and\SpecialChar \slash{}
+or font failures.
+ Again, LyX cannot determine this in advance, so you might need to experiment.
\end_layout
\begin_layout Standard
-Les options pour le choix des polices sont
+
+\lang english
+If you use TeX fonts (which is the default),
+\lang french
+les options pour le choix des polices sont
\family sans
défaut
\family default
\end_layout
\begin_layout Itemize
-Un moyen est d'utiliser des polices
+Utiliser les polices
+\family typewriter
+Latin Modern
+\family default
+ (
+\family typewriter
+lm
+\family default
+).
+ Ces polices ont été développées à la demande de la communauté LaTeX pour
+ remplacer les polices
+\family typewriter
+cm
+\family default
+ comme polices implicites.
+ Dans la plupart des cas elles ressemblent aux polices
+\family typewriter
+cm
+\family default
+
+\begin_inset Foot
+status collapsed
+
+\begin_layout Plain Layout
+Une différence est un crénage amélioré avec les polices
+\family typewriter
+lm
+\family default
+.
+\end_layout
+
+\end_inset
+
+, mais
+\family typewriter
+lm
+\family default
+ couvre un grand nombre de caractères issus des deux familles
+\family typewriter
+cm
+\family default
+ et
+\family typewriter
+ec
+\family default
+.
+\end_layout
+
+\begin_layout Itemize
+Utiliser des polices
+\family typewriter
+AE
+\family default
+(
+\family typewriter
+Almost European
+\family default
+)
+\lang english
+in (the rare) case that
+\family typewriter
+Latin Modern
+\family default
+ is not available to you or does not work, and you still want to emulate
+ the look of
+\family typewriter
+cm
+\family default
+/
+\family typewriter
+ec
+\family default
+.
+
+\lang french
+
\family typewriter
AE
\family default
- qui sont des polices virtuelles.
+ sont des polices virtuelles.
Virtuelle signifie qu'elle
\begin_inset Quotes eld
\end_inset
\end_layout
\begin_layout Itemize
-Une autre possibilité est d'utiliser trois polices contour
-\begin_inset Foot
-status collapsed
-\begin_layout Plain Layout
-Les autres polices comme
+\lang english
+If you do not like the look of
\family typewriter
-Latin Modern
+cm
\family default
- ou
+/
\family typewriter
-Computer Modern
+ec
\family default
-, consistent en ces trois types de polices principaux
-\family sans
-sans
-\begin_inset space ~
+, you can of course select one of the other provided vector fonts, e.
+\begin_inset space \thinspace{}
\end_inset
-serif
-\family default
-,
-\family sans
-chasse
+g.
\begin_inset space ~
\end_inset
-fixe
+
+\family sans
+Times Roman
\family default
-, et
+ or
+\family typewriter
+
\family sans
-serif
+Palatino
\family default
.
-\end_layout
+ Most roman vector fonts will automatically select matching sans
+\begin_inset space ~
+\end_inset
+serif and typewriter fonts
+\begin_inset Foot
+status collapsed
+
+\begin_layout Plain Layout
+
+\lang english
+These are sometimes just matching other fonts (e.
+\begin_inset space \thinspace{}
\end_inset
-:
-\family typewriter
+g.,
+\family sans
Times Roman
\family default
- comme police romane,
+ selects
\family sans
-
+Helvetiva
+\family default
+ for sans serif text), and sometimes, e.
+\begin_inset space \thinspace{}
+\end_inset
+
+g.
+ with
\family typewriter
-Helvetica
+Latin Modern
\family default
- réduite à 92 ou 95
+ or
+\family typewriter
+Computer Modern
+\family default
+, different shapes of the same font, i.
\begin_inset space \thinspace{}
\end_inset
-% comme police
-\begin_inset space ~
+e.
+ a real font
+\emph on
+family
+\emph default
+.
+\end_layout
+
\end_inset
-serif font, et enfin
-\family typewriter
-courier
-\family default
- comme police à chasse fixe.
+, but you can also select your own.
+\lang french
+
\begin_inset Newline newline
\end_inset
livres.
\end_layout
-\begin_layout Itemize
-La meilleure solution est d'utiliser les polices
-\family typewriter
-Latin Modern
-\family default
- (
-\family typewriter
-lm
-\family default
-).
- Ces polices ont été développées à la demande de la communauté LaTeX pour
- remplacer les polices
-\family typewriter
-cm
-\family default
- comme polices implicites.
- Dans la plupart des cas elles ressemblent aux polices
-\family typewriter
-cm
-\family default
-
-\begin_inset Foot
-status collapsed
-
-\begin_layout Plain Layout
-Une différence est un crénage amélioré avec les polices
-\family typewriter
-lm
-\family default
-.
-\end_layout
-
-\end_inset
-
-, mais
-\family typewriter
-lm
-\family default
- couvre un grand nombre de caractères issus des deux familles
-\family typewriter
-cm
-\family default
- et
-\family typewriter
-ec
-\family default
-.
-\end_layout
-
\begin_layout Standard
\begin_inset VSpace bigskip
\end_inset
12
\family default
.
- la taille
+
+\lang english
+Some classes provide additional sizes.
+
+\lang french
+ La taille
\family sans
défaut
\family default
- dépend de votre système LaTeX mais elle est en principe égale à la taille
- 10.
+ dépend de
+\lang english
+the class you are using.
+ In the standard classes
+\lang french
+ elle est égale à la taille 10.
\end_layout
\begin_layout Standard
.
\end_layout
+\begin_layout Standard
+
+\lang english
+The
+\family sans
+Default Family
+\family default
+ selection lets you specify whether the base font of your document should
+ be roman, sans
+\begin_inset space ~
+\end_inset
+
+serif or typewriter.
+ The
+\family sans
+Default
+\family default
+ selection uses what is preset by the class, the other selections override
+ this.
+ In most cases,
+\family sans
+Default
+\family default
+ is equal to
+\family sans
+roman
+\family default
+, but some classes (such as presentation classes) also use other defaults.
+\end_layout
+
+\begin_layout Standard
+
+\lang english
+The
+\family typewriter
+
+\family sans
+LaTe
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+{}
+\end_layout
+
+\end_inset
+
+X font encoding
+\family default
+ selection is an expert setting which lets you change the value passed to
+ the LaTeX-package
+\emph on
+fontenc
+\emph default
+.
+ Normally, you do not need to change (or even understand) this.
+ Unless you have specific reasons use
+\family sans
+Default
+\family default
+.
+\end_layout
+
+\begin_layout Standard
+
+\lang english
+With some fonts, the checkboxes
+\family sans
+Use Old Style Figures
+\family default
+ and
+\family sans
+Use True Small Caps
+\family default
+ are enabled.
+ These are extra features some fonts provide.
+ If
+\family sans
+Use Old Style Figures
+\family default
+ is checked, the font uses old style (also known as medieval or text) figures,
+ i.
+\begin_inset space \thinspace{}
+\end_inset
+
+e.
+\begin_inset space ~
+\end_inset
+
+figures with varying height that fit nicely with lower letters.
+
+\family sans
+Use True Small Caps
+\family default
+ determines that real small caps are used instead of faked small caps made
+ of scaled capitals.
+ Real small caps are often part of expert font sets; they generally look
+ better than faked small caps but might have to be purchased separately.
+\end_layout
+
\begin_layout Standard
Le champ
\family sans
.
\begin_inset Foot
-status open
+status collapsed
\begin_layout Plain Layout
La police sera l'argument des commandes du paquetage LaTeX
(ps2ascii)
\family default
-ce dernier faisant d'abord une conversion en PostScript avant d'utiliser
-
-\series bold
-ps2ascii
-\series default
- pour le transformer en texte simple.
+ce dernier faisant d'abord une conversion en PostScript avant le transformation
+ en texte simple.
\end_layout
\begin_layout Subsubsection
\family sans
Fichier\SpecialChar \menuseparator
Exporter\SpecialChar \menuseparator
-DVI.
+DVI
+\family default
+ou
+\family sans
+Fichier\SpecialChar \menuseparator
+Exporter\SpecialChar \menuseparator
+DVI
+\begin_inset space ~
+\end_inset
+
+(LuaTe
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+{}
+\end_layout
+
+\end_inset
+
+X).
+
+\family default
+
+\lang english
+The latter option uses the program
+\family typewriter
+LuaTeX
+\family default
+.
+
+\family typewriter
+LuaTeX
+\family default
+ is an engine that provides direct Unicode support and support for direct
+ font access (see section
+\begin_inset space ~
+\end_inset
+
+
+\begin_inset CommandInset ref
+LatexCommand ref
+reference "sub:LaTeX-font-support"
+
+\end_inset
+
+).
+ LuaTeX is still work in progress, but it might develop into the next standard
+ TeX processor.
\end_layout
\begin_layout Subsubsection
qui convertit directement votre fichier en PDF.
\end_layout
+\begin_layout Description
+PDF
+\begin_inset space ~
+\end_inset
+
+(XeTe
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+{}
+\end_layout
+
+\end_inset
+
+X)
+\lang english
+This uses the program
+\family typewriter
+XeTeX
+\family default
+ that converts your file directly to PDF.
+
+\family typewriter
+XeTeX
+\family default
+ is a new engine that provides direct Unicode support and support for direct
+ font access (see section
+\begin_inset space ~
+\end_inset
+
+
+\begin_inset CommandInset ref
+LatexCommand ref
+reference "sub:LaTeX-font-support"
+
+\end_inset
+
+).
+ It is particularly good at typesetting different scripts.
+\end_layout
+
+\begin_layout Description
+PDF
+\begin_inset space ~
+\end_inset
+
+(LuaTe
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+{}
+\end_layout
+
+\end_inset
+
+X)
+\lang english
+This uses the program
+\family typewriter
+LuaTeX
+\family default
+ that converts your file directly to PDF.
+
+\family typewriter
+LuaTeX
+\family default
+ is an even newer engine, derived from
+\family typewriter
+pdflatex
+\family default
+, that also provides direct Unicode support and support for direct font
+ access (see section
+\begin_inset space ~
+\end_inset
+
+
+\begin_inset CommandInset ref
+LatexCommand ref
+reference "sub:LaTeX-font-support"
+
+\end_inset
+
+).
+ LuaTeX is still work in progress, but it might develop into the next standard
+ tex processor.
+\end_layout
+
\begin_layout Standard
Nous recommandons d'utiliser l'option
\family sans
\family default
accepte toutes les fonctionnalités des versions actuelles de PDF.
Il est en plus rapide et stable.
- Le programme
+
+\lang english
+If you rely on multiscript support and\SpecialChar \slash{}
+or specific OpenType fonts, you might
+ want to try out
+\family sans
+PDF
+\begin_inset space ~
+\end_inset
+
+(XeTe
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+{}
+\end_layout
+
+\end_inset
+
+X)
+\family default
+ or
+\family sans
+PDF
+\begin_inset space ~
+\end_inset
+
+(LuaTe
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+{}
+\end_layout
+
+\end_inset
+
+X)
+\family default
+ instead, bearing in mind that these two programs are not yet as mature
+ as
\family typewriter
-dvipdfm
+pdflatex
\family default
- n'est plus développé est est donc un peu dépassé.
+.
\end_layout
\begin_layout Standard
\begin_layout Standard
\begin_inset Formula \[
-A=B\]
+A=B
+\]
\end_inset
\lambda_{1}\\
& \ddots\\
& & \lambda_{n}
-\end{array}\right)\]
+\end{array}\right)
+\]
\end_inset
\left[\frac{1}{\left(\begin{array}{cc}
2 & 3\\
4 & 5
-\end{array}\right)}\right]\]
+\end{array}\right)}\right]
+\]
\end_inset
\begin_layout Standard
\begin_inset Formula \[
-\sum_{n=1}^{\infty}\frac{x^{n}}{n}=\ln\left(\frac{1}{1-x}\right)\]
+\sum_{n=1}^{\infty}\frac{x^{n}}{n}=\ln\left(\frac{1}{1-x}\right)
+\]
\end_inset
\begin_layout Standard
\begin_inset Formula \[
-\int_{-\infty}^{\infty}\frac{dx}{1+x^{2}}=\pi\]
+\int_{-\infty}^{\infty}\frac{dx}{1+x^{2}}=\pi
+\]
\end_inset
\begin_layout Standard
\begin_inset Formula \[
-\lim_{x\rightarrow\infty}f(x)\]
+\lim_{x\rightarrow\infty}f(x)
+\]
\end_inset
\left[\begin{array}{cc}
1 & 2\\
3 & 4
-\end{array}\right]\]
+\end{array}\right]
+\]
\end_inset
\begin_layout Standard
\begin_inset Formula \[
-\frac{1}{\left(1+\left(\frac{1}{1+\left(\frac{1}{1+x}\right)}\right)\right)}\]
+\frac{1}{\left(1+\left(\frac{1}{1+\left(\frac{1}{1+x}\right)}\right)\right)}
+\]
\end_inset
\begin_layout Standard
\begin_inset Formula \[
-f\left(g\left(h\left(k\left(l\left(x\right)\right)\right)\right)\right)\]
+f\left(g\left(h\left(k\left(l\left(x\right)\right)\right)\right)\right)
+\]
\end_inset
1 & 2 & 3\\
4 & 5 & 6\\
7 & 8 & 9
-\end{array}\right)\]
+\end{array}\right)
+\]
\end_inset
\textrm{cette} & \textrm{cette colonne} & \textrm{cette colonne}\\
\textrm{colonne} & \textrm{est} & \textrm{est alignée}\\
\textrm{est alignée à gauche} & \textrm{centrée} & \textrm{à droite}
-\end{array}\]
+\end{array}
+\]
\end_inset
-1 & x<0\\
0 & x=0\\
1 & x>0
-\end{cases}\]
+\end{cases}
+\]
\end_inset
\begin_layout Standard
\begin_inset Formula \begin{eqnarray*}
-\frac{A}{B} & \frac{A}{B} & \frac{A}{B}\end{eqnarray*}
+\frac{A}{B} & \frac{A}{B} & \frac{A}{B}
+\end{eqnarray*}
\end_inset
Dans ce document les numéros sont en principe imprimés avec le numéro du
chapitre, séparés par un point:
\begin_inset Formula \begin{equation}
-1+1=2\end{equation}
+1+1=2
+\end{equation}
\end_inset
\family default
représente l'ensemble des entiers naturels :
\begin_inset Formula \[
-f(x)=\sqrt{x}\:;\: x\in\mathbb{N}\]
+f(x)=\sqrt{x}\:;\: x\in\mathbb{N}
+\]
\end_inset
f(x)=\begin{cases}
x & \textrm{dans ce cas là}\\
-x & \textrm{dans l'autre cas}
-\end{cases}\]
+\end{cases}
+\]
\end_inset
\series default
apparaît:
\begin_inset Formula \[
-x^{2}-2x-2\Rightarrow\question{x_{1}}\reponse{x_{2}}=1\question{+\sqrt{3}}\reponse{-\sqrt{3}}.\]
+x^{2}-2x-2\Rightarrow\question{x_{1}}\reponse{x_{2}}=1\question{+\sqrt{3}}\reponse{-\sqrt{3}}.
+\]
\end_inset
d'un encodage dans le fichier LaTeX.
Si vous n'utilisez pas cette option, alors tout le document utilisera toujours
un seul encodage.
- Activer cette option est le meilleur choix, à moins que vous n'utilisiez
-
-\family sans
-XeTeX
-\begin_inset Foot
-status collapsed
-
-\begin_layout Plain Layout
-
-\family sans
-XeTeX
-\family default
-est un programme de mise en forme
-\family sans
- TeX,
-\family default
-une alternative à
-\family sans
- LaTeX.
-
-\family default
-Il gère de façon native Unicode et ses fichiers d'entrée sont supposés être
- en encodage UTF-8.
- On trouvera plus d'information au sujet de LyX et XeTeX dans
-\begin_inset CommandInset citation
-LatexCommand cite
-key "XeTeX"
-
-\end_inset
-
-.
-\end_layout
-
-\end_inset
-
-
-\family default
- (voir plus bas).
+ Activer cette option est le meilleur choix.
\end_layout
\begin_layout Standard
marche pas avec un encodage utf8 fixé (quand la liste de commandes LaTeX
connues n'est pas utilisée, puisque tous les symboles Unicode peuvent être
encodés en utf8).
+
+\lang english
+The situation is much better with XeTeX and LuaTeX, two new alternative
+ engines to standard LaTeX.
+ Both engines support Unicode natively.
+ LyX now also supports these two engines (via the output formats
+\family sans
+PDF
+\begin_inset space ~
+\end_inset
+
+(XeTe
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+{}
+\end_layout
+
+\end_inset
+
+X)
+\family default
+,
+\family sans
+PDF
+\begin_inset space ~
+\end_inset
+
+(LuaTe
+\begin_inset ERT
+status collapsed
+
+\begin_layout Plain Layout
+
+{}
+\end_layout
+
+\end_inset
+
+X)
+\family default
+ and
+\family sans
+DVI
+\begin_inset space ~
+\end_inset
+
+(LuaTeX)
+\family default
+; see section
+\begin_inset space ~
+\end_inset
+
+
+\begin_inset CommandInset ref
+LatexCommand ref
+reference "sec:Formats-des-fichiers-en-sortie"
+
+\end_inset
+
+), so if the above options fail, you might try out one of these new engines.
\end_layout
\begin_layout Standard
\family sans
XeTeX
\family default
-qui utilise Unicode directement, sans l'aide du paquetage LaTeX
+et
+\family sans
+LuaTeX
+\family default
+ qui utilisent Unicode directement, sans l'aide du paquetage LaTeX
\series bold
inputenc
\series default
-
-\begin_inset Foot
-status collapsed
-
-\begin_layout Plain Layout
-Plus d'information pour utiliser LyX avec XeTeX dans
-\begin_inset CommandInset citation
-LatexCommand cite
-key "XeTeX"
-
-\end_inset
-
.
-\end_layout
-
-\end_inset
-
-
+
+\lang english
+LyX automatically selects this encoding if you export or preview XeTeX or
+ LuaTeX.
+ Normally you do not need to set this encoding manually.
\end_layout
\begin_layout Description
\end_inset
-\end_layout
-
-\begin_layout Bibliography
-\labelwidthstring Bibliographie
-\begin_inset CommandInset bibitem
-LatexCommand bibitem
-key "XeTeX"
-
-\end_inset
-
-
-\begin_inset CommandInset href
-LatexCommand href
-name "page Wiki"
-target "http://wiki.lyx.org/LyX/XeTeX"
-
-\end_inset
-
- comment utiliser LyX avec XeTeX:
-\begin_inset Newline newline
-\end_inset
-
-
-\begin_inset Flex URL
-status collapsed
-
-\begin_layout Plain Layout
-
-http://wiki.lyx.org/LyX/XeTeX
-\end_layout
-
-\end_inset
-
-
\end_layout
\begin_layout Bibliography