diff --git a/tenet/febTransduction/net/net.py b/tenet/febTransduction/net/net.py
index 207f3a777e9e3b0c0fcca46bc50cbf0c77a555bf..3753c204ea392783f02afe9f1af6d0876d7fbf96 100644
--- a/tenet/febTransduction/net/net.py
+++ b/tenet/febTransduction/net/net.py
@@ -80,10 +80,11 @@ class Net:
     def get_attribute_value(self, **attr):
         
         res = None
+        
         for attr_key, attr_value in attr.items():
-            if attr_value == None:
+            if (self.uri is not None) & (attr_value is None):
                 res = self.__select_value_in_graph(attr_key)
-            elif attr_value == []:
+            elif (self.uri is not None) & (attr_value == []):
                 res = self.__select_value_list_in_graph(attr_key)
             else:
                 res = attr_value
diff --git a/tenet/febTransduction/phenomena_application_or.py b/tenet/febTransduction/phenomena_application_or.py
index f8aed303bfab31221022549838202cdd5cc467e0..fe469053bdd528c92a228f1c3ef4dce1fba8c69c 100644
--- a/tenet/febTransduction/phenomena_application_or.py
+++ b/tenet/febTransduction/phenomena_application_or.py
@@ -100,7 +100,7 @@ def analyze_phenomena_or_1(graph):
         composite_class_net.compose(class_net, property_net, phenomena_net)
     
         # -- Data Computation
-        composite_class_net.mother_class = class_net
+        composite_class_net.mother_class = class_net.uri
         # etc
     
         # -- Restriction Computation