Christian Erbach junior (1604-1645) was the son of Christian Erbach (~1570 – 1635). Where his father left a considerable amount of music, only a few works of Erbach junior have survived the years. Erbach junior was organist of the Augsburger Dom from 1636 till his death in 1645. Since Wolfgang Agricola filled the post for a year after the death of Erbach senior, Erbach junior was not the immediate successor of his father. The Organbook of Mattias Rottenau contains one canzona with Erbach junior named as composer.
Score available here: http://partitura.org/index.php/christian-erbach-junior-canzona-secundi-toni/