https://www.jstor.org/stable/25194549?searchText=Abu+Muslim+Coin&searchUri=%2Faction%2FdoBasicSearch%3FQuery%3DAbu%2BMuslim%2BCoin&ab_segments=0%2Fbasic_search_gsv2%2Fcontrol&refreqid=fastly-default%3Ad1c6b49e8ce5c250e6ac273716da2ee5&seq=1#metadata_info_tab_contents