*[http://web.archive.org/web/20080516185655/http://answering-islam.org.uk/Books/Tisdall/Sources0/p011-012.htm Jewish Sources of the Qur'an]*[http://web.archive.org/web/20070814220855/http://answering-islam.org.uk/Books/Tisdall/Sources/chap3chapt3.htm Influence of Sabian and Jewish ideas and practices.]