docs: function (obj, obj2, data) {
      if(!this.hasNode(obj.id)) { this.addNode(obj); }
      if(!this.hasNode(obj2.id)) { this.addNode(obj2); }
      obj = this.nodes[obj.id]; obj2 = this.nodes[obj2.id];
      var adjsObj = this.edges[obj.id] = this.edges[obj.id] || {};
      var adjsObj2 = this.edges[obj2.id] = this.edges[obj2.id] || {};
      adjsObj[obj2.id] = adjsObj2[obj.id] = new Graph.Adjacence(obj, obj2, data, this.Edge, this.Label);
      return adjsObj[obj2.id];
   }