diff --git a/src/docs/asciidoc/prob_handbook.adoc b/src/docs/asciidoc/prob_handbook.adoc
index b4eb4dcaecc771bbb810c3c56d2df086eee55a9c..3a9141283059fc95d41394faf918e22f6840bd90 100644
--- a/src/docs/asciidoc/prob_handbook.adoc
+++ b/src/docs/asciidoc/prob_handbook.adoc
@@ -3,7 +3,7 @@ Jens Bendisposto;Joy Clark;Michael Leuschel
 :bibtex-file: combined.bib
 :coderay-linenums-mode: table
 :doctype: book
-:icon: font
+:icons: font
 :imagesdir: images
 :linkattrs:
 :source-highlighter: coderay