Source: HradKM 7, pp. 56-63. Edition: Lenka Mrácková, ed., Missa Introduxit me rex in cellam vinariam, Hudební veda, 43/2 (Prague: Dept. of Music History, Inst. of Ethnology, Acad. of Sciences of the Czech Republic, 2006). I [Wegman] am most grateful to Dr Mrácková for sending me a copy of her edition. The manuscript attributes the "credo" to Yacten, and the "sanctus" to Eleganzer. The dates of composition listed above correspond to the dates of the source. See: http://www.arts.ufl.edu/motet/sources_music.asp