Biblio
] , „Dr. Hans Popper, An Authority On Liver Diseases, Is Dead At 84 (Obituary)“, New York Times, New York Times (gehalten auf der May 8, 1988, New York, 1988) <https://www.nytimes.com/1988/05/08/obituaries/dr-hans-popper-an-authority-on-liver-diseases-is-dead-at-84.html>