Saya mau tau Rujukan dari Haji. Jelaskan dalam bahasa sunda

Khan, Qaisra, "Hajj & 'Umra", in Muhammad in History, Thought, and Culture: An Encyclopedia of the Prophet of God (2 vols.), edited by C. Fitzpatrick and A. Walker, Santa Barbara, ABC-CLIO, 2014, Vol. I, pp. 239–245.