References
- World Health Organization. Risk approach for maternal and child health care. World Health Organization, Geneva 1978, WHO Offset Publication No. 39
- Samueloff A, Mor-Yosef S, Seidman D S, Adler I, Persitz E, Schenker J G. Ranking risk factors for perinatal mortality: Analysis of a nation-wide study. Acta Obstet Gynecol Scand 1989; 68: 677–682