anchor.diff:  
   del_node_t(#occi_node{id=Id, type=occi_collection, objid=#uri{}, data=Col}=Node) ->
       lists:foreach(fun (#uri{}=ChildId) ->
  -			  case mnesia:wread({occi_node, ChildId}) of
  -			      [] -> 
  -				  ignore;
  -			      [#occi_node{}=Child] ->
  -				  del_node_t(Child)
  -			  end
  -		  end, occi_collection:get_entities(Col)),
  +						  case mnesia:wread({occi_node, ChildId}) of
  +							  [] -> 
  +								  ignore;
  +							  [#occi_node{}=Child] ->
  +								  del_node_t(Child)
  +						  end
  +				  end, occi_collection:get_entities(Col)),
       del_from_collection_t(occi_node:get_parent(Node), Id),
       mnesia:delete({occi_node, Id});
   
  
positive.code: 
  load_object_t(Node, Type, Id) ->
      case mnesia:wread({Type, Id}) of
  	[] ->
  	    mnesia:abort({unknown_object, {Type, Id}});
  	[Data] ->
  	    Node#occi_node{data=Data}
      end.
  
  
  
negative.code: 
  add_to_collection_t(#uri{path=Path}=Parent, Child) ->
      case mnesia:wread({occi_node, Parent}) of
  		[] ->
  			mnesia:write(occi_node:new(Parent, occi_collection:new(Parent, [Child])));
  		[#occi_node{type=occi_collection, data=#occi_collection{}=Coll}=Node] ->
  			mnesia:write(Node#occi_node{data=occi_collection:add_entity(Coll, Child)});
  		[#occi_node{}] ->
  			mnesia:abort({unknown_collection, Parent})
      end,
      if Path == [] -> ok;
         true -> add_to_collection_t(occi_uri:get_parent(Parent), {collection, Parent})
  