From the Introduction:
The texts of Aman used in the preparation of this edition are taken from five editions of Montchrestien's plays, i.e., 1601, 1603, 1604, 1606, 1627. There are, however, in fact only two editions which differ from each other, i.e., the 1601 and 1604 editions. . . . In the arrangement of the present text in this edition of texts of [the editions of 1601 and 1604] are printed on opposite pages.