"Īlkhāns," from Encyclopaedia of Islam (1986), in 9 searchable pdf pages. B. Spuler describes the history of this Mongol dynasty which ruled Iran in the 13th and 14th centuries; and R. Ettinghausen describes Ilkhanid architecture and art. Uploaded by Robert Bedrosian. Wikipedia has an entry on the Ilkhanate; and Encyclopaedia Iranica has numerous studies on the Il-khans. A selection of works on the Mongols at Internet Archive is here.