diff --git a/ChangeLog b/ChangeLog
index c34527616..3be332d0a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,7 @@
 2005-01-29  Alexandre Duret-Lutz  <adl@gnu.org>
 
+	* src/tgbaalgos/gtec/gtec.hh (couvreur99_check): Document poprem.
+
 	* bench/emptchk/README: Make clearer that spin is needed.
 
 	* src/tgbatest/randtgba.cc (syntax): Missing std::endl.
diff --git a/src/tgbaalgos/gtec/gtec.hh b/src/tgbaalgos/gtec/gtec.hh
index 594296b17..610c0e8f2 100644
--- a/src/tgbaalgos/gtec/gtec.hh
+++ b/src/tgbaalgos/gtec/gtec.hh
@@ -73,6 +73,15 @@ namespace spot
   /// tgba_succ_iterators: it must compute all successors of a state
   /// at once in order to decide which to explore first, and must keep
   /// a list of all unexplored successors in its DFS stack.
+  ///
+  /// The \c poprem parameter specifies how the algorithm should
+  /// handle the destruction of non-accepting maximal strongly
+  /// connected components.  If \c poprem is true, the algorithm will
+  /// keep a list of all states of a SCC that are fully processed and
+  /// should be removed once the MSCC is popped.  If \c poprem is
+  /// false, the MSCC will be traversed again (i.e. generating the
+  /// successors of the root recursively) for deletion.  This is
+  /// a choice between memory and speed.
   class couvreur99_check: public emptiness_check, public ec_statistics
   {
   public: