Complex sentence: His special study of the choral music of Thomas Tomkins was published in Musica Deo Sacra; another major work was his editing of Handel's oratorio Susanna (Kassel 1967).
Split into simpler sentences: His special study of the choral music of Thomas Tomkins was published in Musica Deo Sacra. Another major work was his editing of Handel's oratorio Susanna (Kassel 1967).