Sometimes the same subject is represented by more than one matter bond
Sometimes the same subject is represented by more than one matter bond. This can be the case when two matter charts are amalgamated. In such a situation it is necessary to have a certain manner of proving the identity between the apparently disparate matters. For example, if the editors of work of reference of Norway, of Denmark, of Poland and Germany were to amalgamate their matter charts, there would be a need to be able to affirm that the matters Spania, Spanien and Hiszpania all are referred to the same subject.