diff --git a/eo/src/gp/Makefile.am b/eo/src/gp/Makefile.am
index bdbf6a66..d4b58753 100644
--- a/eo/src/gp/Makefile.am
+++ b/eo/src/gp/Makefile.am
@@ -5,4 +5,4 @@
 ###############################################################################
 
 libeoincdir = $(includedir)/eo/gp
-libeoinc_HEADERS = eoParseTree.h  node_pool.h parse_tree.h
+libeoinc_HEADERS = eoParseTree.h  node_pool.h parse_tree.h eoGpMutate.h