Title: Juzʾ fīhi Shurūṭ Amīr al-Muʾminīn ʻUmar ibn al-Khaṭṭāb. Wa-fīhi Ḥadīth Wāṣil al-Dimashqī wa-munāẓarātuhu la-hum. Riwāyat Abī ʻAmr wa-ʻUthmān ibn Aḥmad al-Sammāk