Brown 2009, p. 129. "Ibn al-Muqaffaʿ, the son of an Iraqi tax collector who had been tortured for mishandling tax revenues (hence the nickname "al-Muqaffaʿ", the cripple), was happy to oblige." Brown, Daniel W. (2009). A New Introduction to Islam (2nd ed.). Wiley-Blackwell. ISBN978-1405158077.