diff --git a/Bezout.hs b/Bezout.hs
--- a/Bezout.hs
+++ b/Bezout.hs
@@ -1,17 +1,34 @@
-module Bezout(-- *  Extended gcd of integers
+module Bezout (
+-- *  Extended gcd of integers
 besout ,
 -- * Modular inverse of integer
-inverseMod,shift,pad,trim,trim' ,deg,(+:),mods,mMod,
+inverseMod,
+-- * shift
+shift,
+-- * pad
+pad,
+-- * trim
+trim,
+-- * trim'
+trim' ,
+-- * deg
+deg,
+-- * (+:)
+(+:),
+-- * mods
+mods,
+-- * mMod
+mMod,
 -- * Multiplication of polynomials in F_p[x]
 multPolyZ,
 -- * Euclidean division of polynomials for F_p[x]
-		euclideanPolyMod, 
+euclideanPolyMod, 
 -- * Extended gcd of polynomials in F_p[x]
 extendedgcdpoly ,
 -- * Inverse of polynomial P modulo polynomial Q in F_p[x]
-		inversePolyMod,
+inversePolyMod,
 -- * Pretty form  polynom input
-prettyFormPoly) where
+prettyFormPoly ) where
 
 -- besout
 -- | besout compute extended gcd of two integers. For example : "besout" 13 17 = [4,-3,1] , this means that 
@@ -28,24 +45,26 @@
 inverseMod x y = let a = besout x y in
 		case a!!2 of 1 -> mods (a!!0) y
 			     _ -> 0
-
--- | rightpad
+-- shift
+-- | padding left with n zeros
 shift n l = l ++ replicate n 0
--- | leftpad
+-- pad
+-- | padding right with n zeros
 pad n l = replicate n 0 ++ l
 -- | trim
 trim x = dropWhile (== 0) x
 -- | trim'
 trim' x = let y = trim x in if y == [] then [0] else y
 -- deg
--- | deg 
+-- | degree of polynomial 
 deg l = length (trim l) - 1
 -- | (+:) add or abstract two list of different length
 (+:) op p q = let d = (length p) - (length q) in zipWith op (pad (-d) p) (pad d q)
+-- mods
 -- | mods return positve remainder of "mod" operator
 mods :: Integer -> Integer -> Integer
 mods x p = if y >= 0 then y else y + p where y = mod x p 
-
+-- mMod
 -- | mMod map "mods" over list of integers
 mMod :: [Integer]-> Integer ->[Integer]
 mMod [] _ = []
@@ -57,15 +76,21 @@
 --To compute the product of polynomials P,Q we borrow the Horner multiplication rules as described by the following chain.
 --It consists to do n compositions of functions detailed in the following diagramm:
 --Q -> anxQ + a_(n-1)Q
+--
 --	R -> xR + a_(n-2)Q
+--
 --		R -> xR + a_(n-3)Q
+--
 --			R -> xR + a-1Q
+--
 --				...
---				R -> xR + a_0Q
+--
+--					R -> xR + a_0Q
+--
 --Let f = [2,0,3,2,1::Integer], g = [2,5,-3,1::Integer] in F_7[x].
 --"multPolyZ 7 f g" = [4,3,0,0,3,2,6,1] . 
 -- That means that f*g = 4*x^7 + 3*x^6 + 3*x^3 + 2*x^2 + 6*x + 1  in F_7[x].
--- Be careful to always use the decreasing order in writing polynoms for multPolyZ .
+-- This function require writing polynoms in decreasing order .
 multPolyZ :: Integer ->[Integer]->[Integer]-> [Integer]
 multPolyZ _ [0] _ = [0]
 multPolyZ _ _ [0] = [0]
@@ -106,7 +131,9 @@
 -- | "extendedgcdpoly" compute the extended gcd of polynomials P and Q in the ring F_p[x] where p is a prime number. 
 -- Let f = [2,0,3,2,1::Integer], g = [2,5,-3,1::Integer] in F_7[x]. 
 -- "extendedgcdpoly" 7 f g = [[5,3],[2,6,5],[2,1]] .
--- This means that the gcd of f and g in F_7[x] is the polynom 2*x+1 , and 2*x + 1 = (5*x + 3)*f + (2*x^2 + 6*x + 5)*g in F_7[x].
+-- This means that the gcd of f and g in F_7[x] is the polynom 2*x+1 , and
+--
+-- 2 * x + 1 = (5 * x + 3) * f + (2 * x^2 + 6 * x + 5) * g in F_7[x].
 
 extendedgcdpoly :: Integer -> [Integer] -> [Integer] -> [[Integer]]
 extendedgcdpoly p x y = let t = besoutPoly p x y in let z = t!!2 in
@@ -123,13 +150,16 @@
 -- "extendedgcdpoly" 13 f g =[[7,3,7],[6,8,4,7],[1]].
 -- So f and g are relatively prime in F_13[x] , and the inverse of f modulo g in F_13[x] is given by 
 -- "inversePolyMod" 13 f g = [7,3,7] . 
+--
 -- Which says that the inverse of ploynomial f denoted f^(-1) is 7*x^2 + 3*x + 7 modulo g in F_13[x]
 inversePolyMod :: Integer -> [Integer] -> [Integer] -> [Integer]
 inversePolyMod p x y = let t = extendedgcdpoly p x y in let z = length $ t!!2 in 
 			case z of 1 -> t!!0
 				  _ -> [0]
 -- prettyFormPoly
--- | This is a facility for writing non nul terms of polynomial , if f = 5*x^13 + 4*x^5 + (-3)*x^4 + 11*x + 19 , then prettyFormPoly [[5,13],[4,5],[-3,4],[11,1],[19,0]] = [5,0,0,0,0,0,0,0,4,-3,0,0,11,19]
+-- | This is a facility for writing non nul terms of polynomial , if f = 5*x^13 + 4*x^5 + (-3)*x^4 + 11*x + 19 , then
+--
+-- prettyFormPoly [[5,13],[4,5],[-3,4],[11,1],[19,0]] = [5,0,0,0,0,0,0,0,4,-3,0,0,11,19]
 
 prettyFormPoly :: [[Integer]]->[Integer]
 prettyFormPoly [[]] = []
diff --git a/besout.cabal b/besout.cabal
--- a/besout.cabal
+++ b/besout.cabal
@@ -10,7 +10,7 @@
 -- PVP summary:      +-+------- breaking API changes
 --                   | | +----- non-breaking API additions
 --                   | | | +--- code changes with no API change
-version:             0.1.0.0
+version:             0.2.0.0
 
 -- A short (one-line) description of the package.
 synopsis:            Extended GCD of polynomials over F_p[x]
@@ -50,5 +50,5 @@
   -- other-modules:       
   
   -- Other library packages from which modules are imported.
-  build-depends:       base ==4.5.*
+  build-depends:       base ==4.6.*