↑ Tʻang Studies Society. Studies in early Medieval Chinese literature and cultural history : in honor of Richard B. Mather & Donald Holzman, 2003. ISBN 978-0-9729255-0-1.
↑The Iggeres of Rav Sherira Gaon (en anglès). Jerusalem: Rabbi Jacob Joseph School Press - Ahavath Torah Institute Moznaim, 1988, p. 100. OCLC923562173.