Mukhtasar Muslim

It is narrated from Sayyiduna Ibn Abbas (may Allah be pleased with them both) that the Noble Prophet (peace and blessings be upon him) said to a woman from among the Ansar, who was called Umm Sinan: "Why do you not go with us for Hajj?" She replied, "My husband has only two camels; he and his son have gone for Hajj on one, and our servant brings water on the other." So the Prophet (peace and blessings be upon him) said, "Umrah in Ramadan is equal to Hajj (or he said: equal to performing Hajj with us)."