Niehaus, F. J. (2001). Karl's diary: Blessed Karl Leisner: in his own words. Schoenstatt Fathers.
Chicago-Zitierstil (17. Ausg.)Niehaus, Fr Jonathan. Karl's Diary: Blessed Karl Leisner: In His Own Words. Waukesha, WI: Schoenstatt Fathers, 2001.
MLA-Zitierstil (8. Ausg.)Niehaus, Fr Jonathan. Karl's Diary: Blessed Karl Leisner: In His Own Words. Schoenstatt Fathers, 2001.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.