src/Doc/ROOT

--- a/src/Doc/ROOT	Wed Mar 16 21:11:15 2016 +0100
+++ b/src/Doc/ROOT	Wed Mar 16 21:14:59 2016 +0100
@@ -357,7 +357,7 @@
 session System (doc) in "System" = Pure +
   options [document_variants = "system", thy_output_source]
   theories
-    Basics
+    Environment
     Sessions
     Presentation
     Scala