Rudolf Otto Neumann 1868–1952 Source: Wikimedia Commons About Rudolf Otto Neumann German hygienist People from the Same Era Otto Pötzl 1877–1962 neurologist, psychiatrist, university teacher Vienna Flóra Örley 1861–1940 actor, opera singer Oradea Yamakawa Gitarō 1860–1933 Saitama Prefecture Johannes Müller 1864–1949 theologian Riesa Alfonso de Cal 1877–1937 journalist, jurist, politician Ferrol Celestin Rousseau 1861–1949 Esperantist, pharmacist Le Portel