Zantinga, Arty R.; Coppes, Max J. (1993). „James Ewing (1866–1943): "the chief"”. Medical and Pediatric Oncology. 21 (7): 505—510. PMID8341219. doi:10.1002/mpo.2950210709.
Zantinga, Arty R.; Coppes, Max J. (1993). „James Ewing (1866–1943): "the chief"”. Medical and Pediatric Oncology. 21 (7): 505—510. PMID8341219. doi:10.1002/mpo.2950210709.