diff --git a/MANIFEST.in b/MANIFEST.in
index 1432104e80aec3ee869da6c195a197b427985ff5..1686fff42b87132f49ef97580297ef0ca07f5843 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -3,6 +3,7 @@ include isl/*.h
 include isl/imath/*.c
 include isl/imath/*.h
 include isl/imath_wrap/*.h
+include isl/imath_wrap/*.c
 include isl/include/isl/*.h
 include isl/include/isl/deprecated/*.h
 include isl-supplementary/isl/*.h