Berko, Matthew A..
Catholic Church. Liturgy and ritual.
The order for the celebration of Vespers, Matins, and the Divine Liturgy according to the Ruthenian recension /
Matthew A. Berko 
. - Washington : [s. n.],  1958 
. - 122 p.  22 cm. 
<br/><br/> A translation of "Ordo celebrationis Vesperarum, Matutini, et Divinae Liturgiae iuxta recensionem Ruthenorum" published by the Sacred Congregation for the Eastern Church, Rome 1944.