diff --git a/src/tgba/tgbabddconcretefactory.hh b/src/tgba/tgbabddconcretefactory.hh
index 02e6b8703..c3276c066 100644
--- a/src/tgba/tgbabddconcretefactory.hh
+++ b/src/tgba/tgbabddconcretefactory.hh
@@ -28,7 +28,7 @@ namespace spot
     /// \param f The formula to create an aotmic proposition for.
     /// \return The variable number for this state.
     ///
-    /// The atomic proposition is not created if it already exists.  
+    /// The atomic proposition is not created if it already exists.
     /// Instead its existing variable number is returned.  Variable numbers
     /// can be turned into BDD using ithvar().
     int create_atomic_prop(const ltl::formula* f);
diff --git a/src/tgba/tgbabddconcreteproduct.hh b/src/tgba/tgbabddconcreteproduct.hh
index 78eabf250..5ee1ab10b 100644
--- a/src/tgba/tgbabddconcreteproduct.hh
+++ b/src/tgba/tgbabddconcreteproduct.hh
@@ -7,7 +7,7 @@ namespace spot
 {
   /// \brief Multiplies two tgba::tgba_bdd_concrete automata.
   ///
-  /// This function build the resulting product, as another 
+  /// This function build the resulting product, as another
   /// tgba::tgba_bdd_concrete automaton.
   tgba_bdd_concrete
   product(const tgba_bdd_concrete& left, const tgba_bdd_concrete& right);
diff --git a/src/tgba/tgbabddcoredata.hh b/src/tgba/tgbabddcoredata.hh
index aac99c2e4..1ea06c8e2 100644
--- a/src/tgba/tgbabddcoredata.hh
+++ b/src/tgba/tgbabddcoredata.hh
@@ -27,7 +27,7 @@ namespace spot
     /// \brief The (positive) conjunction of all variables which are
     /// not Now variables.
     bdd notnow_set;
-    /// \brief The (positive) conjunction of all variables which are 
+    /// \brief The (positive) conjunction of all variables which are
     /// not atomic propositions.
     bdd notvar_set;
     /// The (positive) conjunction of all variables which are not promises.
diff --git a/src/tgba/tgbabddtranslatefactory.hh b/src/tgba/tgbabddtranslatefactory.hh
index d1b41eb47..1e34c0be5 100644
--- a/src/tgba/tgbabddtranslatefactory.hh
+++ b/src/tgba/tgbabddtranslatefactory.hh
@@ -6,7 +6,7 @@
 
 namespace spot
 {
-  
+
   /// A spot::tgba_bdd_factory than renumber BDD variables.
   class tgba_bdd_translate_factory: public tgba_bdd_factory
   {