diff --git a/pymath/calculus/abstract_polynom.py b/pymath/calculus/abstract_polynom.py
index 03eb601..b6a1ac0 100644
--- a/pymath/calculus/abstract_polynom.py
+++ b/pymath/calculus/abstract_polynom.py
@@ -292,7 +292,8 @@ class AbstractPolynom(Explicable):
         """
         if (isNumber(other) and not isPolynom(other)) or \
             (isPolynom(other) and self._letter != other._letter):
-                ans = self.__class__([other], letter=self._letter)
+                #ans = self.__class__([other], letter=self._letter)
+                ans = AbstractPolynom([other], letter=self._letter)
                 ans.steal_history(other)
                 return ans
         elif isPolynom(other):
@@ -326,6 +327,23 @@ class AbstractPolynom(Explicable):
         6 x^{  2 } + 12 x + 3
         >>> Q.steps
         [< Step [6, 'x', 2, ^, *, 3, 'x', *, +, 4, 'x', *, +, 5, 'x', *, +, 1, +, 2, +]>, < Step [6, 'x', 2, ^, *, 3, 4, +, 5, +, 'x', *, +, 1, 2, +, +]>, < Step [6, 'x', 2, ^, *, 7, 5, +, 'x', *, +, 3, +]>, < Step [6, 'x', 2, ^, *, 12, 'x', *, +, 3, +]>]
+        >>> P = AbstractPolynom([1,2])
+        >>> Q = AbstractPolynom([P,3], 'y')
+        >>> Q
+        < AbstractPolynom y [< AbstractPolynom x [1, 2]>, 3]>
+        >>> Q = Q.reduce()
+        >>> for i in Q.explain():
+        ...    print(i)
+        3 y + 2 x + 1
+        >>> P = AbstractPolynom([1,2])
+        >>> Q = AbstractPolynom([[P,1],3], 'y')
+        >>> Q
+        < AbstractPolynom y [[< AbstractPolynom x [1, 2]>, 1], 3]>
+        >>> Q = Q.reduce()
+        >>> for i in Q.explain():
+        ...    print(i)
+        3 y + 2 x + 1 + 1
+        3 y + 2 x + 2
         """
 
         # TODO: Il manque le ini_step |jeu. mars 10 12:39:40 EAT 2016
@@ -426,6 +444,16 @@ class AbstractPolynom(Explicable):
         3 x^{  2 } + 7 x + 5
         >>> R.steps
         [< Step [3, 'x', 2, ^, *, 2, 'x', *, +, 1, +, 5, 'x', *, 4, +, +]>, < Step [3, 'x', 2, ^, *, 2, 'x', *, +, 5, 'x', *, +, 1, +, 4, +]>, < Step [3, 'x', 2, ^, *, 2, 5, +, 'x', *, +, 1, 4, +, +]>, < Step [3, 'x', 2, ^, *, 7, 'x', *, +, 5, +]>]
+        >>> Q = AbstractPolynom([4,5], letter = 'y')
+        >>> R = P+Q
+        >>> R
+        < AbstractPolynom x [< AbstractPolynom y [5, 5]>, 2, 3]>
+        >>> for i in R.explain():
+        ...    print(i)
+        3 x^{  2 } + 2 x + 1 + 5 y + 4
+        3 x^{  2 } + 2 x + 5 y + 1 + 4
+        3 x^{  2 } + 2 x + 5 y + 5
+
         """
         o_poly = self.conv2poly(other)