1. Frere G: Mean age of menopause and menarche in South Africa. South African Journal of Medical Sciences. 1971, 36: 21-4.
2. Mekinlay SM, Feffreys K, Thompson B: An I nvestigation of the age of menopause. Journal of Biosocial Sciences. 1972, 4: 161-3.
3. Whitehead MI: Menopause. Dewhurst's Textbook of Obstetrics and Gynaecology for Postgraduate Students. Edited by: Edmonds DK. 1999, Edinburgh. Blackwell Science, 441-6
4. Brincat M, Savvas M, Studd J: The menopause. Clinical Gynaecology. Edited by: Varma TR. 1990, London. Edward Arnold, 742.
5. Maclennan AH, Broadbent JL, Lester S, Moore V: Oral estrogen and combined estrogen/progestogen therapy versus placebo for hot flushes. Cochrane Data Base Syst Rev. 2004, 18 (4): C.D002978.