Yazid bin Ibrahim narrated that I heard Imam Hasan al-Basri, may Allah have mercy on him, say about the person who does not fast during the days of Ramadan: He must offer expiation by freeing a slave, or slaughtering a camel, or giving twenty sa’ (approximately 45 kilograms) of grain to forty needy people. And the same expiation is obligatory upon the person who has intercourse with his wife while she is menstruating.
Hadith Referenceسنن دارمي / من كتاب الطهارة / 1140
Hadith Takhrijسند اس اثر کی صحیح ہے۔ دیکھئے: [ابن أبى شيبه 12378]
Brief Explanation
(Commentary on Hadith 1139) That is, for such a person as well, the expiation is to free a slave, or to slaughter a camel, or to give twenty saa‘ of charity. This is their statement, not a hadith.