Flexner, Simon, 1863-1946 William Henry Welch and the heroic age of American medicine / by Simon Flexner and James Thomas Flexner. - New York : The Viking Press , 1941, 1956. - x, 539 p. : plates, ports. ; 24 cm. First published in October 1941. Subjects--Personal Names: Welch, William Henry, 1850-1934. -------- National Library of Medicine Call No.: DY / W443fl