Is the book "Al-Umm" by Al-Shafi'i incomplete or missing parts? And does reading "Al-Risala," "Mukhtasar al-Muzani," "Al-Umm," and all that Al-Shafi'i wrote cover all his works and dictations? And where can one read his books that were mentioned in his biography in Al-Bayhaqi's "Manaqib" and "Tawali al-Ta'sis"?

There is no knowledge of any omission or deficiency in Imam Shafi'i's Kitab al-Umm. Dr. Ahmad Badr al-Din Hassoun has authenticated Kitab al-Umm and its appended books of differences, which are nine books. Imam Shafi'i's books number around 140, divided into old (written in Baghdad and Mecca) and new (written in Egypt). These books can be reviewed on the website islamport, and one can benefit from the library of books and research available on the forums of Ahl al-Hadith and the Shafi'i School. It is recommended to refer to Imam Shafi'i's books themselves to benefit from the valuable jurisprudential branches.