diff --git a/thys/Forcing/ROOT b/thys/Forcing/ROOT
--- a/thys/Forcing/ROOT
+++ b/thys/Forcing/ROOT
@@ -1,21 +1,21 @@
 chapter AFP
 
-session Forcing (AFP) =  "ZF-Constructible" +
+session Forcing (AFP) = "ZF-Constructible" +
   description "
     Formalization of Forcing in Isabelle/ZF
 
     We formalize the theory of forcing in the set theory framework of
     Isabelle/ZF. Under the assumption of the existence of a countable
     transitive model of ZFC, we construct a proper generic extension
     and show that the latter also satisfies ZFC.
   "
-  options [timeout=300]
+  options [timeout = 300]
   theories [document = false]
     Utils
   theories
     "Rasiowa_Sikorski"
     "Forcing_Main"
   document_files
     "root.tex"
     "root.bib"
     "root.bst"