--- a/src/Doc/ROOT Sat Dec 16 20:02:40 2017 +0100
+++ b/src/Doc/ROOT Sat Dec 16 21:53:07 2017 +0100
@@ -372,6 +372,8 @@
session System (doc) in "System" = Pure +
options [document_variants = "system", thy_output_source]
+ sessions
+ "HOL-Library"
theories
Environment
Sessions