of a mixed rite after the return of the court and the patriarchate from the exile in Nikaia in 1261, had nothing really innovative with respect the sign repertoire of Middle Byzantine notation. The innovation was probably already done outside Constantinople, in those monastic scriptoria whose scribes cared about the lost cathedral rite and did integrate different forms of Old Byzantine notation (those of the sticherarion and heirmologion like theta notation, Coislin and Chartres type as well as those of the Byzantine asmatikon and kontakarion which were based on cheironomies). The argument was mainly based on the astonishing continuity that a new a type of treatise revealed by its continuous presence from the 13th to the 19th centuries: the Papadike. In a critical edition of this huge corpus, Troelsgård together with Maria Alexandru discovered many different functions that this treatise type could have. It was originally an introduction for a revised type of sticherarion, but it also introduced many other books like mathemataria (literally "a book of exercises" like a sticherarion kalophonikon or a book with heirmoi kalophonikoi, stichera kalophonika, anagrammatismoi and kratemata), akolouthiai (from "taxis ton akolouthion" which meant "order of services", a book which combined the choir book "asmatikon", the book of the soloist "kontakarion", and with the rubrics the instructions of the typikon) and the Ottoman anthologies of the Papadike which tried to continue the tradition of the notated book akolouthiai (usually introduced by a Papadike, a kekragarion/anastasimatarion, an anthology for Orthros, and an anthology for the divine liturgies). With the end of creative poetical composition, Byzantine chant entered its final period, devoted largely to the production of more elaborate musical settings of the traditional repertoire: either embellishments of the earlier simpler melodies (palaia "old"), or original music in highly ornamental style (called "kalophonic"). This was the work of the so-called Maïstores, "masters", of whom the most celebrated was St. John Koukouzeles (14th century) as a famous innovator in the development of chant. The multiplication of new settings and elaborations of the traditional repertoire continued in the centuries following the fall of Constantinople. The revision of the chant books One part of this process was the redaction and limitation of the present repertoire given by the notated chant books of the sticherarion (menaion, triodion, pentekostarion, and oktoechos) and the heirmologion during the 14th century. Philologists called this repertoire the "standard abridged version" and counted alone 750 stichera