正教真诠

zhèng jiào zhēn quán

Exegesis of the Right Religion by Wang Daiyu 王岱輿|王岱舆[Wang2 Dai4 yu2], a study of Islam published during the Ming dynasty

正

zhèng

straight

教

jiào

(bound form) to teach; to instruct

真

zhēn

really

诠

quán

to explain