Though the pioneering music theory of Marchetto da Padova was written in this early period, the influence of his treatise on notation, the "Pomerium", is largely seen in the manuscripts of the succeeding generations. Marchetto, building on the innovations of Petrus de Cruce, described a system of division of the breve into 2, 3, 4, 6,8, 9, or 12 semibreves (later minims) with dots (singular "punctus divisionis") indicating breaks at the end of a breve (however, Marchetto never used a term 'punctus divisionis'). Although more Trecento music is written in the international system of notation descended from Franco of Cologne and Philippe de Vitry than in the Marchettian system (and there exist a few, mostly instrumental, works not of Italian origin that use this system), nonetheless, Marchetto's contribution to rhythmic notation is so connected with the Italian Trecento that it is often referred to as simply, "Italian Notation."