diff --git a/monadic-recursion-schemes.cabal b/monadic-recursion-schemes.cabal
--- a/monadic-recursion-schemes.cabal
+++ b/monadic-recursion-schemes.cabal
@@ -4,7 +4,7 @@
 -- http://haskell.org/cabal/users-guide/
 
 name:                monadic-recursion-schemes
-version:             0.1.11.0
+version:             0.1.12.0
 synopsis:            Recursion Schemes for Monadic version.
 description:         Yet another recursion schemes for monadic style, depends on recursion-schemes.
 homepage:            https://github.com/cutsea110/monadic-recursion-schemes.git
@@ -28,7 +28,7 @@
                        GADTs,
                        LambdaCase,
                        ScopedTypeVariables
-  build-depends:       base ^>=4.12.0.0,
+  build-depends:       base >=4.12.0.0 && <4.14,
                        containers >=0.6,
                        mtl >=2.2.2,
                        transformers >=0.5.6,
@@ -44,4 +44,4 @@
   type:                exitcode-stdio-1.0
   hs-source-dirs:      test
   main-is:             MyLibTest.hs
-  build-depends:       base ^>=4.12.0.0
+  build-depends:       base >=4.12.0.0 && <4.14
diff --git a/src/Data/Functor/Foldable/Monadic.hs b/src/Data/Functor/Foldable/Monadic.hs
--- a/src/Data/Functor/Foldable/Monadic.hs
+++ b/src/Data/Functor/Foldable/Monadic.hs
@@ -295,6 +295,7 @@
 gcataM k g = liftM extract . cataM phi
   where phi = mapM g <=< k <=< return . fmap duplicate
 
+-- | generalized catamorphism variant
 gcataM' :: (Monad m, Comonad w, Traversable w, Traversable (Base t), Recursive t, b ~ w a)
         => (Base t (w b) -> m (w (Base t b))) -- ^ Distributive (Base t) w b
         -> (Base t (w a) -> m a)              -- ^ algebra