diff --git a/mapytex/calculus/core/tree.py b/mapytex/calculus/core/tree.py
index aa32bb2..a6cda98 100644
--- a/mapytex/calculus/core/tree.py
+++ b/mapytex/calculus/core/tree.py
@@ -863,7 +863,7 @@ class LeafTree(Tree):
 class AssocialTree(Tree):
 
     """ Tree which concider every subtree with a node different from itself
-    as a Lead
+    as a Leaf
     """
     def map_on_leaf(self, function):
         """ Map on leafs a function
diff --git a/mapytex/calculus/core/tree_tools.py b/mapytex/calculus/core/tree_tools.py
index 88db950..5c1a880 100644
--- a/mapytex/calculus/core/tree_tools.py
+++ b/mapytex/calculus/core/tree_tools.py
@@ -85,7 +85,6 @@ def show_tree(op, left, right, sep = "|", node_caracter = ">"):
     right_slided = leaf_suffix.join(str(right).splitlines())
     return node_suffix.join([op, left_slided, right_slided])
 
-
 # -----------------------------
 # Reglages pour 'vim'
 # vim:set autoindent expandtab tabstop=4 shiftwidth=4: