71. Sunan Ibn Majah 72. Ibn Hajar al-Haythami, Al-Qawl al-Mukhtasar, 23 73. Sidney Fox, Klaus Dose, Molecular Evolution and The Origin of Life, W. H. Freeman and Company, San Francisco, 1972, p. 4
Zaidi ya hayo, unazo riwaya zake katika Sahih Muslim na vitabu vinne vya Sunan kutokea Hakim, Al-A'mash na Fudayl ibn 'Amr kama zilivyo rekodiwa na Muslim, Sufyan ibn 'Uyaynah, Sha'bah na Idris al-Awdi.