Eugène Gley (1857–1930), French physiologist and endocrinologist
After graduation Heymans worked at the Collège de France (under Prof. E. Gley), the University of Lausanne (under Prof. M. Arthus), the University of Vienna (under Prof. H. H. Meyer), University College London (under Prof. E. H. Starling) and Case Western Reserve University School of Medicine (under Prof. C. F. Wiggers).