diff --git a/koch-backbuch.pdf b/koch-backbuch.pdf
index f57a27a..042e8b3 100644
--- a/koch-backbuch.pdf
+++ b/koch-backbuch.pdf
Binary files differ
diff --git a/koch-backbuch.tex b/koch-backbuch.tex
index 7b7f990..0d9b82c 100644
--- a/koch-backbuch.tex
+++ b/koch-backbuch.tex
@@ -8,7 +8,9 @@
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %% FONTENCODING
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+\usepackage[sfdefault]{FiraSans}
 \usepackage[T1]{fontenc}
+\renewcommand*\oldstylenums[1]{{\firaoldstyle #1}}
 \usepackage[utf8x]{inputenc}
 \usepackage{lmodern}
 \usepackage[ngerman]{babel}