Books by Ingrid Semmingsen

That is from Ingrid Semmingsen, Norway to America: A History of the Migration , and I believe the original reference is to ” Immigration and Insanity: A Study of Mental Disease Among the Norwegian-born Population of Minnesota,” Ø Ødegaard – Acta psychiatrica Scandinavica, Suppl, 1932.”  Here is a related post on gene-culture interaction .