RT Journal Article SR Electronic T1 Seasonal distribution of abortions. JF British Journal of Preventive & Social Medicine JO Br J Prev Soc Med FD BMJ Publishing Group Ltd SP 222 OP 224 DO 10.1136/jech.25.4.222 VO 25 IS 4 A1 A D McDonald YR 1971 UL http://jech.bmj.com/content/25/4/222.abstract AB