Kitab al-Amwal (The Book of Revenue)
One of the earliest works on public finance in Islam, the best known being that of Abu Ubayd al-Qasim ibn Sallam (d. 224 AH). It deals with fay, the land tax, the poll tax, zakat and the rules on property, and includes material on dirhams and dinars and their weights.
Abu Ubayd (al-Qasim ibn Sallam)