Worldcat lists a string quartet Op.14, an opera in manuscript by Zech "Ein Sommerabend am Rhein" "before 1932". Mentioned as alive in Wier's "The Macmillan encyclopedia of music and musicians" (1938) (which contains a brief biography: "Zech, Fritz, German organist, vocal teacher and composer, born Polzin, Dec. 20, 1875 ; he has written orchestral music, a 'cello concerto, chamber music and choruses.")
