"...If the party liable is mentally deficient, or weak, or unable Himself to dictate, Let his guardian dictate faithfully, and get two witnesses, out of your own men, and if there are not two men, then a man and two women, such as ye choose, for witnesses, so that if one of them errs, the other can remind her. The witnesses should not refuse when they are called on (For evidence)." - Quran 2:282 (read more)

"And he [Muhammad] had their hands and feet cut off. Then he ordered for nails which were heated and passed over their eyes, and whey were left in the Harra (i.e. rocky land in Medina). They asked for water, and nobody provided them with water till they died (Abu Qilaba, a sub-narrator said, 'They committed murder and theft and fought against Allah and His Apostle, and spread evil in the land.')" - Sahih Bukhari 1:3:63 (read more)

"The people of Iraq ... do not come out with something between blonde, buff and blanched coloring, such as the infants dropped from the wombs of the women of the Slavs and others of similar light complexion; nor are they overdone in the womb until they are burned, so that the child comes out something between black, murky, malodorous, stinking, and crinkly-haired, with uneven limbs, deficient minds, and depraved passions, such as the Zanj, the Somali, and other blacks who resemble them." - Ibn al-Faqih