o:1684852
Persistent identifier https://phaidra.univie.ac.at/o:1684851
Handle https://hdl.handle.net/11353/10.1684851
URI https://valep.vc.univie.ac.at/virtualarchive/public/Philipp_Frank_Institute_for_the_Unity_of_Science_to_Morris_1950-08-22_L/d:952571