Coba jelasin Catatatan kaki dari Kekaisaran Khwarezmia dong

M. Ismail Marcinkowski, Persian Historiography and Geography: Bertold Spuler on Major Works Produced in Iran, the Caucasus, Central Asia, India and Early Ottoman Turkey, with a foreword by Professor Clifford Edmund Bosworth, member of the British Academy, Singapore: Pustaka Nasional, 2003, ISBN 9971-77-488-7.