United States. Children's Bureau and Allen, Nila F. (Nila Frances), 1875-1964. Infant Mortality : Results of a Field Study in Saginaw, Mich., Based on Births in One Year, Infant Mortality Series No. 9, Bureau Publication No. 52 , Washington, D.C: Government Printing Office, 1919, https://fraser.stlouisfed.org/title/8340, accessed on December 25, 2025.