However , various later IbÄ á Ä `` leaders are recognized as true imÄ ms , including Abdullah ibn Yahya al-Kindi of South Arabia and the imÄ ms of the Rustamid dynasty in North Africa . However , various later Ibadi leaders are recognized as true imams , including Abdullah ibn Yahya al-Kindi of South Arabia and the imams of the Rustamid dynasty in North Africa .