Richardson, Clement (1919). "A. Wilberforce Williams, M.D.". The National Cyclopedia of the Colored Race. National Publishing Company. p. 150.
britannica.com
"Howard T. Ricketts". Encyclopædia Britannica. Encyclopædia Britannica Online Academic Edition. Encyclopædia Britannica Inc. Retrieved November 28, 2011.
Wang, Andrew (February 19, 2013). "ChicagoBusiness.com". N'western Memorial gives largest grant to namesake university. Crain's. Retrieved June 3, 2016.
Wiedemann HR (March 1993). "The pioneers of pediatric medicine. Isaac Arthur Abt (1867-1955)". European Journal of Pediatrics. 152 (3): 177. doi:10.1007/BF01956138. PMID8444239. S2CID32960382.
Wiedemann HR (March 1993). "The pioneers of pediatric medicine. Isaac Arthur Abt (1867-1955)". European Journal of Pediatrics. 152 (3): 177. doi:10.1007/BF01956138. PMID8444239. S2CID32960382.
Wiedemann HR (March 1993). "The pioneers of pediatric medicine. Isaac Arthur Abt (1867-1955)". European Journal of Pediatrics. 152 (3): 177. doi:10.1007/BF01956138. PMID8444239. S2CID32960382.