I got the name off of my Mother's birth certificate...it listed Hazel Cameron Zelter as the mother of Barbara Jean Kaiser. So there wasn't any other info about Hazel other than there were 4 existing siblings to my Mother, and in 1930, this birth was in Hackensack, NJ....and Hazel listed NJ as her birth place. Yours is the only response I've had about Zelter name. If you come accross anything else, please let me know. Thanks!