https://fas.francke-halle.de/cgi-bin/gkdb.pl?x=u&t_show=x&wertreg=PER&wert=klingner%2C%20curt%20%20-%20BIOGRAFIE&reccheck=154725
https://www.ancestry.com.au/search/categories/img_passlists/?name=_klingner&srsltid=AfmBOoqIdPSUIS7i3lsD3se42QeJ6SOGBsCF-dlXaXJEB10s39be8tO-