(33, 34) باب ذِكْرِ الاِخْتِلاَفِ عَلَى خَالِدٍ الْحَذَّاءِ
It was narrated from Ya'qub bin Aws, from a man among the Companions of the Prophet that:
when the Messenger of Allah entered Makkah on the Day of the Conquest, he said: "Indeed, every accidental killing on purpose, or resembling on purpose - killing with a whip or stick, for it are forty (she-camels) which their young in their wombs."
Reference: Sunan an-Nasa'i 4796
In-book reference: Book 45, Hadith 91
English translation: Vol. 5, Book 45, Hadith 4800