Secular changes in mean birth weights in the ten largest cities of Japan. Single births, 1969-1980
わが国の大都市における平均出生時体重の年次推移 単産,1969‐1980年

Toru Doi, Hiroaki Kahyo, Shinya Matsuda, Tomofumi Sone
1987 Nippon Eiseigaku Zasshi (Japanese Journal of Hygiene)  
doi:10.1265/jjh.42.894 fatcat:p7p4hvi2sbbpnjbwlycvly4gua