Discantus and Altus part-books (sign. NM-CMH AZ 84) were made by the later binding of component parts consisting of four prints and five manuscripts from the 1540s through about the 1590s. For the first time, the professional community can familiarize itself with their external description and contents. Those contents consist predominantly of compositions intended for Vespers (Magnificat settings and hymns). Special attention is paid to two Magnificat settings Bohemian Christmas and Easter songs in the discant part. For each of the twelve songs, the oldest known incidences of their melody and text were identified, and transcriptions of the songs are also included. The discant part-book AZ 84 represents an indispensable source for the genesis of some of the songs (Všem věc divná, neslýchaná [To All Something Strange, Unheard-Of], Hory se zelenají [The Hills Turn Green], Plešíc již všecko stvoření [All Creation Now Rejoicing], Šalomúnovy postele šedesáte ostříhalo [Sixty Men around Solomons Bed]), Dagmar Štefancová., Rubrika: Studie, and Anglické resumé na s. 22.