United States. Children's Bureau
and Duke, Emma, 1876-.
Infant Mortality : Results of the Field Study in Johnstown, PA., based on Births in One Calendar Year, Infant Mortality Series No. 3, Bureau Publication No. 9 ,
Washington, D.C:
Government Printing Office,
1915, https://fraser.stlouisfed.org/title/8302,
accessed on December 24, 2025.