Is central religious text of Islam?

The authoritative text of Islam as per preference are:
1. The holy Qur'an - the last heavenly holy book revealed to the last prophet of Islam Hazrat Muhammad (SAW). It is the final Word of Almighty God. Unchangeable.
2. The authentic volumes of books of the sayings of the holy Prophet (SAW). Sihah-i- Sitta. Six books considered to contain most authentic sayings of the Prophet (SAW)
3. Islamic Jurisprudence (Fiqah) inferred and compiled by Four Imams (Scholars) of Fiqah.