Sources
The parents Dr. Leo and Ida Pins
The article contains numerous sources and a detailed biography of Dr. Leo Pins and his wife Ida Pins (née Lipper).
Fritz Ostkämper: Die Eltern Dr. Leo und Ida Pins, geb. Lipper, Forum Jacob Pins im Adelshof, 2017, available at: http://www.jacob-pins.de/?article_id=34&clang=0
