Kenneth Mah e Yitzchak M Binik, The nature of human orgasm: a critical review of major trends, in Clinical Psychology Review, vol. 21, n. 6, 7 gennaio 2001, pp. 823-856, DOI:10.1016/S0272-7358(00)00069-6, PMID 11497209.
«Women rated clitoral stimulation as at least somewhat more important than vaginal stimulation in achieving orgasm; only about 20% indicated that they did not require additional clitoral stimulation during intercourse.»