Sources
Photos and biographical information on Helene, Margot and Hannelore Adler
Stolpersteine (commemorative plaques) were laid in Gießen for Helene, Margot and Hannelore Adler. The municipal website provides photos of the Adler family and short biographical texts.
Universitätsstadt Gießen: Stolpersteine in der Nordanlage 49 für Helene, Margot und Hannelore Adler, online available at: https://www.giessen.de/Erleben/%C3%9Cber-Gie%C3%9Fen/Stolpersteine/Nordanlage-49.php?object=tx,2874.1320.1&ModID=7&FID=2874.1347.1&NavID=2874.396&La=1
