diff --git a/Data/IntMap/Unicode.hs b/Data/IntMap/Unicode.hs
--- a/Data/IntMap/Unicode.hs
+++ b/Data/IntMap/Unicode.hs
@@ -1,16 +1,46 @@
-{-# LANGUAGE UnicodeSyntax #-}
+{-# LANGUAGE NoImplicitPrelude, UnicodeSyntax #-}
 
+{-|
+Module     : Data.IntMap.Unicode
+Copyright  : (c) 2009–2010 Roel van Dijk
+License    : BSD3 (see the file LICENSE)
+Maintainer : Roel van Dijk <vandijk.roel@gmail.com>
+-}
+
 module Data.IntMap.Unicode
     ( (∈), (∉)
     , (∅)
     , (∪), (∩)
     ) where
 
+
+-------------------------------------------------------------------------------
+-- Imports
+-------------------------------------------------------------------------------
+
+-- from base:
+import Data.Bool ( Bool  )
+import Data.Int  ( Int )
+
+-- from containers:
 import Data.IntMap ( IntMap
                    , member, notMember
                    , empty
                    , union, intersection
                    )
+
+
+-------------------------------------------------------------------------------
+-- Fixities
+-------------------------------------------------------------------------------
+
+infix  4 ∈
+infix  4 ∉
+
+
+-------------------------------------------------------------------------------
+-- Symbols
+-------------------------------------------------------------------------------
 
 {- |
 (&#x2208;) = 'member'
diff --git a/Data/IntSet/Unicode.hs b/Data/IntSet/Unicode.hs
--- a/Data/IntSet/Unicode.hs
+++ b/Data/IntSet/Unicode.hs
@@ -1,5 +1,12 @@
-{-# LANGUAGE UnicodeSyntax #-}
+{-# LANGUAGE NoImplicitPrelude, UnicodeSyntax #-}
 
+{-|
+Module     : Data.IntSet.Unicode
+Copyright  : (c) 2009–2010 Roel van Dijk
+License    : BSD3 (see the file LICENSE)
+Maintainer : Roel van Dijk <vandijk.roel@gmail.com>
+-}
+
 module Data.IntSet.Unicode
     ( (∈), (∉)
     , (∅)
@@ -8,13 +15,40 @@
     , (⊂), (⊃), (⊄), (⊅)
     ) where
 
-import Prelude.Unicode ( (≢), (∧) )
+
+-------------------------------------------------------------------------------
+-- Imports
+-------------------------------------------------------------------------------
+
+-- from base:
+import Data.Bool     ( Bool, not )
+import Data.Function ( flip )
+import Data.Int      ( Int )
+
+-- from base-unicode-symbols:
+import Data.Eq.Unicode   ( (≢) )
+import Data.Bool.Unicode ( (∧) )
+
+-- from containers:
 import Data.IntSet ( IntSet
                    , member, notMember
                    , empty
                    , union, intersection
                    , isSubsetOf, isProperSubsetOf
                    )
+
+
+-------------------------------------------------------------------------------
+-- Fixities
+-------------------------------------------------------------------------------
+
+infix  4 ∈
+infix  4 ∉
+
+
+-------------------------------------------------------------------------------
+-- Symbols
+-------------------------------------------------------------------------------
 
 {- |
 (&#x2208;) = 'member'
diff --git a/Data/Map/Unicode.hs b/Data/Map/Unicode.hs
--- a/Data/Map/Unicode.hs
+++ b/Data/Map/Unicode.hs
@@ -1,16 +1,46 @@
-{-# LANGUAGE UnicodeSyntax #-}
+{-# LANGUAGE NoImplicitPrelude, UnicodeSyntax #-}
 
+{-|
+Module     : Data.Map.Unicode
+Copyright  : (c) 2009–2010 Roel van Dijk
+License    : BSD3 (see the file LICENSE)
+Maintainer : Roel van Dijk <vandijk.roel@gmail.com>
+-}
+
 module Data.Map.Unicode
     ( (∈), (∉)
     , (∅)
     , (∪), (∩)
     ) where
 
+
+-------------------------------------------------------------------------------
+-- Imports
+-------------------------------------------------------------------------------
+
+-- from base:
+import Data.Bool ( Bool )
+import Data.Ord  ( Ord )
+
+-- from containers:
 import Data.Map ( Map
                 , member, notMember
                 , empty
                 , union, intersection
                 )
+
+
+-------------------------------------------------------------------------------
+-- Fixities
+-------------------------------------------------------------------------------
+
+infix  4 ∈
+infix  4 ∉
+
+
+-------------------------------------------------------------------------------
+-- Symbols
+-------------------------------------------------------------------------------
 
 {- |
 (&#x2208;) = 'member'
diff --git a/Data/Sequence/Unicode.hs b/Data/Sequence/Unicode.hs
--- a/Data/Sequence/Unicode.hs
+++ b/Data/Sequence/Unicode.hs
@@ -1,17 +1,31 @@
-{-# LANGUAGE UnicodeSyntax #-}
+{-# LANGUAGE NoImplicitPrelude, UnicodeSyntax #-}
 
+{-|
+Module     : Data.Sequence.Unicode
+Copyright  : (c) 2009–2010 Roel van Dijk
+License    : BSD3 (see the file LICENSE)
+Maintainer : Roel van Dijk <vandijk.roel@gmail.com>
+-}
+
 module Data.Sequence.Unicode
     ( (∅)
     , (⊲), (⊳)
     , (⋈)
     ) where
 
+
+-------------------------------------------------------------------------------
+-- Imports
+-------------------------------------------------------------------------------
+
+-- from containers:
 import Data.Sequence ( Seq
                      , empty
                      , (<|), (|>)
                      , (><)
                      )
 
+
 -------------------------------------------------------------------------------
 -- Fixities
 -------------------------------------------------------------------------------
@@ -19,6 +33,7 @@
 infixr 5 ⋈
 infixr 5 ⊲
 infixl 5 ⊳
+
 
 -------------------------------------------------------------------------------
 -- Symbols
diff --git a/Data/Set/Unicode.hs b/Data/Set/Unicode.hs
--- a/Data/Set/Unicode.hs
+++ b/Data/Set/Unicode.hs
@@ -1,5 +1,12 @@
-{-# LANGUAGE UnicodeSyntax #-}
+{-# LANGUAGE NoImplicitPrelude, UnicodeSyntax #-}
 
+{-|
+Module     : Data.Set.Unicode
+Copyright  : (c) 2009–2010 Roel van Dijk
+License    : BSD3 (see the file LICENSE)
+Maintainer : Roel van Dijk <vandijk.roel@gmail.com>
+-}
+
 module Data.Set.Unicode
     ( (∈), (∉)
     , (∅)
@@ -8,13 +15,41 @@
     , (⊂), (⊃), (⊄), (⊅)
     ) where
 
-import Prelude.Unicode ( (≢), (∧) )
+
+-------------------------------------------------------------------------------
+-- Imports
+-------------------------------------------------------------------------------
+
+-- from base:
+import Data.Bool     ( Bool, not )
+import Data.Function ( flip )
+import Data.Ord      ( Ord )
+
+
+-- from base-unicode-symbols:
+import Data.Eq.Unicode   ( (≢) )
+import Data.Bool.Unicode ( (∧) )
+
+-- from containers:
 import Data.Set ( Set
                 , member, notMember
                 , empty
                 , union, intersection
                 , isSubsetOf, isProperSubsetOf
                 )
+
+
+-------------------------------------------------------------------------------
+-- Fixities
+-------------------------------------------------------------------------------
+
+infix  4 ∈
+infix  4 ∉
+
+
+-------------------------------------------------------------------------------
+-- Symbols
+-------------------------------------------------------------------------------
 
 {- |
 (&#x2208;) = 'member'
diff --git a/LICENSE b/LICENSE
--- a/LICENSE
+++ b/LICENSE
@@ -1,4 +1,4 @@
-Copyright (c) 2009 Roel van Dijk
+Copyright (c) 2009–2010 Roel van Dijk
 
 All rights reserved.
 
diff --git a/containers-unicode-symbols.cabal b/containers-unicode-symbols.cabal
--- a/containers-unicode-symbols.cabal
+++ b/containers-unicode-symbols.cabal
@@ -1,22 +1,19 @@
 name:          containers-unicode-symbols
-version:       0.1
+version:       0.2
 cabal-version: >=1.6
 build-type:    Simple
-stability:     experimental
-author:        Roel van Dijk
-maintainer:    vandijk.roel@gmail.com
-copyright:     (c) 2009 Roel van Dijk
+stability:     provisional
+author:        Roel van Dijk <vandijk.roel@gmail.com>
+maintainer:    Roel van Dijk <vandijk.roel@gmail.com>
+copyright:     (c) 2009–2010 Roel van Dijk <vandijk.roel@gmail.com>
 license:       BSD3
 license-file:  LICENSE
 category:
 synopsis:      Unicode alternatives for common functions and operators
 description:
-
   This package defines new symbols for a number of functions and
   operators in the containers package.
-
   .
-
   All symbols are documented with their actual definition and
   information regarding their Unicode code point. They should be
   completely interchangeable with their definitions.
@@ -31,7 +28,7 @@
                  , Data.Map.Unicode
                  , Data.Sequence.Unicode
                  , Data.Set.Unicode
-
-  build-depends: base >= 3.0.3.1 && < 4.3
-               , base-unicode-symbols == 0.1.*
-               , containers < 0.4
+  build-depends: base                 >= 3.0.3.1 && < 4.3
+               , base-unicode-symbols >= 0.1.1   && < 0.2
+               , containers                         < 0.4
+  ghc-options: -Wall
