diff --git a/src/Utils.hs b/src/Utils.hs
index 80af449b7..4f8b5ff03 100644
--- a/src/Utils.hs
+++ b/src/Utils.hs
@@ -312,7 +312,7 @@ citext2lower = Text.toLower . CI.original
 citext2string :: CI Text -> String 
 citext2string = Text.unpack . CI.original
 
-string2citext :: CI Text -> String 
+string2citext :: String -> CI Text
 string2citext = CI.mk . Text.pack
 
 -- | Convert or remove all non-ascii  characters, e.g. for filenames