Joseph Ewan (1909-1999): a retrospective.
Beidleman
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D001695:Biology / Q000266:history; D004463:Ecology / Q000266:history; D006663:Historiography; D006666:History of Medicine; D049673:History, 20th Century; D019021:Natural History / Q000193:education / Q000266:history / Q000379:methods / Q000458:organization & administration; D014481:United States