diff --git a/doc/geos.sgml b/doc/geos.sgml
index 32996d114..f60d49a67 100644
--- a/doc/geos.sgml
+++ b/doc/geos.sgml
@@ -624,7 +624,7 @@ GEOSLib function (if its type is <tt/char/), but in all cases last error is save
 location. If it is nonzero - an error occured. See <tt/gdisk.h/ for the list of possible errorcodes.
 You need to include <tt/errno.h/ to get <tt/__oserror/, together with standard <tt/errno/. The
 latter gives less verbose, but still usable information and can be used with <tt/strerror/.
-Probably you will get more information using <tt/stroserror/ in similar way.
+Probably you will get more information using <tt/_stroserror/ in similar way.
 <p>
 For passing parameters use almost always pointer to your data e.g. <tt/ReadBuff (&amp;myTrSe)/.