Valentin Rathgeber used different forms for his mass compositions: in Opus I the form of a missa brevis as well as in Opus III and Opus XIX the form of a missa solemnis. Moreover, he distinguishes in Opus XII between the form of a missa ruralis allowing the reduction of the setting without changing the character of the composition, and the form of a missa civilis. In Opus VII Rathgeber has written a different mass for each Marian feast. These compositions display various forms.
This mass is recommended for the feast of Mary's Assumption ...
This mass is recommended for the feast of the Rosary ...