Sahih Muslim Book 8, Hadith Number 3359.

Chapter: It is not permissible to marry a woman, who is divorced by three pronouncements until she is married to another, man and he has a sexual intercourse with her, and then he abandons her and she completes her ‘Idda.

‘A’Asha (Allah be pleased with her) reported: A person divorced his wife by three pronouncements; then another person married her and he also divorced her without having sexual intercourse with her. Then the first husband of her intended to remarry her. It was about such a case that Allah’s Messenger (May peace be upon him) was asked, whereupon he said: No, until the second one has tasted her sweetness as the first one had tasted.