APA

Cuckle H. S., Wald N. J., Densem J. W., Royston P., Knight G. J., Haddow J. E. & Palomaki G. E. (19900612). The effect of smoking in pregnancy on maternal serum alpha-fetoprotein, unconjugated oestriol, human chorionic gonadotrophin, progesterone and dehydroepiandrosterone sulphate levels. : British journal of obstetrics and gynaecology.

Chicago

Cuckle H S, Wald N J, Densem J W, Royston P, Knight G J, Haddow J E and Palomaki G E. 19900612. The effect of smoking in pregnancy on maternal serum alpha-fetoprotein, unconjugated oestriol, human chorionic gonadotrophin, progesterone and dehydroepiandrosterone sulphate levels. : British journal of obstetrics and gynaecology.

Harvard

Cuckle H. S., Wald N. J., Densem J. W., Royston P., Knight G. J., Haddow J. E. and Palomaki G. E. (19900612). The effect of smoking in pregnancy on maternal serum alpha-fetoprotein, unconjugated oestriol, human chorionic gonadotrophin, progesterone and dehydroepiandrosterone sulphate levels. : British journal of obstetrics and gynaecology.

MLA

Cuckle H S, Wald N J, Densem J W, Royston P, Knight G J, Haddow J E and Palomaki G E. The effect of smoking in pregnancy on maternal serum alpha-fetoprotein, unconjugated oestriol, human chorionic gonadotrophin, progesterone and dehydroepiandrosterone sulphate levels. : British journal of obstetrics and gynaecology. 19900612.