diff --git a/docs/NOTES b/docs/NOTES
--- a/docs/NOTES
+++ b/docs/NOTES
@@ -65,11 +65,6 @@
 
 * people probably interested in NumPrelude:
 
- Date: Wed, 28 Oct 2009 21:06:40 -0700
- From: Paul McJones <paul@mcjones.org>
-
- Andrew nochwas aus Wien oder so ...
-
  Mike Thomas <miketh@brisbane.paradigmgeo.com>
    http://www.haskell.org/pipermail/haskell-cafe/2002-February/002660.html
 
@@ -87,17 +82,6 @@
 
  Juergen Bokowski <bokowski@mathematik.tu-darmstadt.de>
    DMV-Nachrichten 2004/3
-
- Gerhard Navratil <Navratil@geoinfo.tuwien.ac.at>
-   Partial derivatives, Haskell-Cafe 2006-05-08
-
- Paul Johnson <paul@cogito.org.uk>
-   interval arithmetic
-   http://sourceforge.net/projects/ranged-sets
-
- David Amos <polyomino@f2s.com>
-   algebra
-   http://polyomino.f2s.com/
 
 * RealFloat
 Defines the properties of a Floating type,
diff --git a/numeric-prelude.cabal b/numeric-prelude.cabal
--- a/numeric-prelude.cabal
+++ b/numeric-prelude.cabal
@@ -1,11 +1,10 @@
 Name:           numeric-prelude
-Version:        0.1.3
+Version:        0.1.3.1
 License:        GPL
 License-File:   LICENSE
 Author:         Dylan Thurston <dpt@math.harvard.edu>, Henning Thielemann <numericprelude@henning-thielemann.de>, Mikael Johansson
 Maintainer:     Henning Thielemann <numericprelude@henning-thielemann.de>
 Homepage:       http://www.haskell.org/haskellwiki/Numeric_Prelude
-Package-URL:    http://darcs.haskell.org/numericprelude/
 Category:       Math
 Stability:      Experimental
 Tested-With:    GHC==6.4.1, GHC==6.8.2
@@ -114,7 +113,7 @@
   the bulk of the functions in Haskell 98's RealFloat class),
   VectorSpace, Ratio, and Lattice.
 Tested-With:    GHC==6.4.1, GHC==6.8.2
-Cabal-Version:  >=1.2
+Cabal-Version:  >=1.6
 Build-Type:     Simple
 
 Extra-Source-Files:
@@ -130,18 +129,27 @@
   description: Build test executables
   default:     False
 
+Source-Repository this
+  Tag:         0.1.3
+  Type:        darcs
+  Location:    http://code.haskell.org/numeric-prelude/
+
+Source-Repository head
+  Type:        darcs
+  Location:    http://code.haskell.org/numeric-prelude/
+
 Library
   Build-Depends:
     parsec >=1 && <3,
-    QuickCheck >=1 && <2,
+    QuickCheck >=1 && <3,
     storable-record >=0.0.1 && <0.1,
     non-negative >=0.0.2 && <0.1,
     utility-ht >=0.0.4 && <0.1
   If flag(splitBase)
     Build-Depends:
-      base >= 2 && <5,
-      array >=0.1 && <0.3,
-      containers >=0.1 && <0.3,
+      base >= 2 && <6,
+      array >=0.1 && <0.4,
+      containers >=0.1 && <0.4,
       random >=1.0 && <1.1
   Else
     Build-Depends: base >= 1.0 && < 2
diff --git a/src/Algebra/Real.hs b/src/Algebra/Real.hs
--- a/src/Algebra/Real.hs
+++ b/src/Algebra/Real.hs
@@ -33,11 +33,6 @@
 
 is not defined.  To me, this seems to have the wrong type anyway;
 Complex.magnitude has the correct type.
-
-Note:
-The abs function can be defined for Additive and Ord,
-the Ring constraint is not needed.
-We may move 'signum' to the new 'RealRing' class.
 -}
 class (Ring.C a, ZeroTestable.C a, Ord a) => C a where
     abs    :: a -> a
diff --git a/src/MathObj/Gaussian/Bell.hs b/src/MathObj/Gaussian/Bell.hs
--- a/src/MathObj/Gaussian/Bell.hs
+++ b/src/MathObj/Gaussian/Bell.hs
@@ -19,7 +19,7 @@
 import Algebra.Ring ((*), (^), )
 import Algebra.Additive ((+), )
 
-import Test.QuickCheck (Arbitrary, arbitrary, coarbitrary, )
+import Test.QuickCheck (Arbitrary, arbitrary, )
 import Control.Monad (liftM4, )
 
 -- import Prelude (($))
@@ -35,7 +35,6 @@
       liftM4
          (\k a b c -> Cons k a b (1 + abs c))
          arbitrary arbitrary arbitrary arbitrary
-   coarbitrary = undefined
 
 
 constant :: Ring.C a => T a
diff --git a/src/MathObj/Gaussian/Polynomial.hs b/src/MathObj/Gaussian/Polynomial.hs
--- a/src/MathObj/Gaussian/Polynomial.hs
+++ b/src/MathObj/Gaussian/Polynomial.hs
@@ -45,7 +45,7 @@
 import Data.List.HT (mapAdjacent, )
 import Data.Tuple.HT (forcePair, )
 
-import Test.QuickCheck (Arbitrary, arbitrary, coarbitrary, )
+import Test.QuickCheck (Arbitrary, arbitrary, )
 import Control.Monad (liftM2, )
 
 import NumericPrelude
@@ -93,7 +93,6 @@
          -- since with the quadratic time algorithms like fourier and convolve,
          -- in connection with Rational slow down tests too much.
          (fmap (Poly.fromCoeffs . take 5 . Poly.coeffs) arbitrary)
-   coarbitrary = undefined
 
 
 
diff --git a/src/MathObj/Gaussian/Variance.hs b/src/MathObj/Gaussian/Variance.hs
--- a/src/MathObj/Gaussian/Variance.hs
+++ b/src/MathObj/Gaussian/Variance.hs
@@ -23,7 +23,7 @@
 import Algebra.Ring ((*), (^), )
 import Algebra.Additive ((+))
 -}
-import Test.QuickCheck (Arbitrary, arbitrary, coarbitrary, )
+import Test.QuickCheck (Arbitrary, arbitrary, )
 import Control.Monad (liftM2, )
 
 -- import Prelude (($))
@@ -39,7 +39,6 @@
       liftM2 Cons
          arbitrary
          (fmap ((1+) . abs) arbitrary)
-   coarbitrary = undefined
 
 
 constant :: Ring.C a => T a
diff --git a/src/MathObj/Polynomial.hs b/src/MathObj/Polynomial.hs
--- a/src/MathObj/Polynomial.hs
+++ b/src/MathObj/Polynomial.hs
@@ -81,7 +81,7 @@
 import Data.List.HT
           (dropWhileRev, switchL, shear, shearTranspose, outerProduct, )
 
-import Test.QuickCheck (Arbitrary(arbitrary,coarbitrary))
+import Test.QuickCheck (Arbitrary(arbitrary))
 
 import qualified Prelude     as P98
 import qualified PreludeBase as P
@@ -426,7 +426,6 @@
 
 instance (Arbitrary a, ZeroTestable.C a) => Arbitrary (T a) where
    arbitrary = liftM (fromCoeffs . normalize) arbitrary
-   coarbitrary = undefined
 
 
 {- * legacy instances -}
diff --git a/src/Number/Complex.hs b/src/Number/Complex.hs
--- a/src/Number/Complex.hs
+++ b/src/Number/Complex.hs
@@ -80,8 +80,8 @@
 import qualified Foreign.Storable.Record as Store
 import Control.Applicative (liftA2, )
 
-import Test.QuickCheck (Arbitrary, arbitrary, coarbitrary)
-import Control.Monad (liftM2)
+import Test.QuickCheck (Arbitrary, arbitrary, )
+import Control.Monad (liftM2, )
 
 import qualified Prelude as P
 import PreludeBase
@@ -125,8 +125,6 @@
 instance (Arbitrary a) => Arbitrary (T a) where
    {-# INLINE arbitrary #-}
    arbitrary = liftM2 Cons arbitrary arbitrary
-   {-# INLINE coarbitrary #-}
-   coarbitrary = undefined
 
 instance (Storable a) => Storable (T a) where
    sizeOf    = Store.sizeOf store
diff --git a/src/Number/GaloisField2p32m5.hs b/src/Number/GaloisField2p32m5.hs
--- a/src/Number/GaloisField2p32m5.hs
+++ b/src/Number/GaloisField2p32m5.hs
@@ -23,7 +23,7 @@
 import qualified Foreign.Storable.Newtype as SN
 import qualified Foreign.Storable as St
 
-import Test.QuickCheck (Arbitrary(..), )
+import Test.QuickCheck (Arbitrary(arbitrary), )
 
 import PreludeBase
 import NumericPrelude
@@ -46,7 +46,6 @@
 
 instance Arbitrary T where
    arbitrary = fmap (Cons . fromInteger . flip mod base) arbitrary
-   coarbitrary = undefined
 
 instance St.Storable T where
    sizeOf = SN.sizeOf decons
diff --git a/src/Number/NonNegative.hs b/src/Number/NonNegative.hs
--- a/src/Number/NonNegative.hs
+++ b/src/Number/NonNegative.hs
@@ -44,7 +44,7 @@
 
 import qualified Algebra.ToInteger          as ToInteger
 import qualified Algebra.ToRational         as ToRational
--- import Test.QuickCheck (Arbitrary(..))
+-- import Test.QuickCheck (Arbitrary(arbitrary))
 
 import qualified Number.Ratio as R
 
@@ -144,7 +144,6 @@
 
 instance (Additive.C a, Arbitrary a) => Arbitrary (T a) where
    arbitrary = liftM (fromNumberUnsafe . abs) arbitrary
-   coarbitrary = undefined
 -}
 
 instance RealIntegral.C a => RealIntegral.C (T a) where
diff --git a/src/Number/NonNegativeChunky.hs b/src/Number/NonNegativeChunky.hs
--- a/src/Number/NonNegativeChunky.hs
+++ b/src/Number/NonNegativeChunky.hs
@@ -39,7 +39,7 @@
 
 import Control.Monad (liftM, liftM2, )
 
-import Test.QuickCheck (Arbitrary(..))
+import Test.QuickCheck (Arbitrary(arbitrary))
 
 import NumericPrelude
 import Data.Tuple.HT (mapFst, mapPair, )
@@ -252,7 +252,6 @@
 
 instance (NonNeg.C a, Arbitrary a) => Arbitrary (T a) where
    arbitrary = liftM Cons arbitrary
-   coarbitrary = undefined
 
 
 
diff --git a/src/Number/Ratio.hs b/src/Number/Ratio.hs
--- a/src/Number/Ratio.hs
+++ b/src/Number/Ratio.hs
@@ -44,7 +44,7 @@
 import qualified Foreign.Storable.Record as Store
 import Control.Applicative (liftA2, )
 
-import Test.QuickCheck (Arbitrary(arbitrary,coarbitrary))
+import Test.QuickCheck (Arbitrary(arbitrary))
 import System.Random (Random(..), RandomGen, )
 
 import qualified Data.Ratio as Ratio98
@@ -160,7 +160,6 @@
    arbitrary =
       liftM2 (%) arbitrary
          (liftM (\x -> if isZero x then one else x) arbitrary)
-   coarbitrary = undefined
 
 
 instance (Storable a, PID.C a) => Storable (T a) where
diff --git a/test/Test/MathObj/PartialFraction.hs b/test/Test/MathObj/PartialFraction.hs
--- a/test/Test/MathObj/PartialFraction.hs
+++ b/test/Test/MathObj/PartialFraction.hs
@@ -70,7 +70,6 @@
    arbitrary =
       let primes = [2,3,5,7,11,13]
       in  fmap SmallPrime $ QC.elements (primes ++ map negate primes)
-   coarbitrary = undefined
 
 instance Show SmallPrime where
    show = show . intFromSmallPrime
@@ -138,7 +137,6 @@
       do poly <- QC.elements (map Poly.fromCoeffs [[2,3],[2,0,1],[3,0,1],[1,-3,0,1]])
          unit <- M.until (not. isZero) QC.arbitrary
          return (IrredPoly (unit Vector.*> poly))
-   coarbitrary = undefined
 
 instance Show IrredPoly where
    show = show . polyFromIrredPoly
