National Perinatal Epidemiology Unit A classified bibliography of controlled trials in perinatal medicine. 1940-1984. Oxford: Oxford University Press, 1986.
Pudendal block in normal vaginal delivery: Clinical efficacy, lidocaine concentration in maternal and foetal blood, foetal and maternal acid-base values and influence on uterine activity
Zandor G, Lindmark G, Nilsson BA. Pudendal block in normal vaginal delivery: clinical efficacy, lidocaine concentration in maternal and foetal blood, foetal and maternal acid-base values and influence on uterine activity. Acta Obstet Gynecol Scand (suppl) 1974;34:51-64.
A randomised controlled trial of care of the perineum during second stage of normal labour
McCandlish R, Bowler U, van Asten H. A randomised controlled trial of care of the perineum during second stage of normal labour. Br J Obstet Gynaecol 1998;105:1262-72.
A randomized study of the sitting position for delivery using a newly designed obstetric chair
Stewart P, Spiby H. A randomized study of the sitting position for delivery using a newly designed obstetric chair. Br J Obstet Gynaecol 1989;96:327-33.