35 only to Muslims and other members of indigenous cultural communities respectively and nothing herein shall be construed to operate to the prejudice of the non-Muslims and non-members of indigenous cultural communities. In case of conflict between the Muslim code and the tribal code, the national law shall apply. In case of conflict between the Muslim code or the tribal code on the one hand, and the national law on the other, the latter shall prevail. Except in cases of successional rights to property, the regular courts shall acquire jurisdiction over controversies involving real property located outside the area of autonomy. Muslims who sue other Muslims or members of indigenous cultural communities who sue other members of indigenous cultural communities over matters covered respectively by Shari'ah or by tribal laws may agree to litigate their grievances before the proper Shari'ah or tribal court in the autonomous region. The procedure for this recourse to the Shari'ah or tribal court shall be prescribed by the Supreme Court. SEC. 23. Bases for Interpretation of Islamic Law. – Subject to the provisions of the Constitution, the Shari'ah courts shall interpret Islamic law based on sources such as: (a) Al-Qur'an (The Koran); (b) Al-Sunnah (Prophetic traditions); (c) Al-Qiyas (Analogy); and (d) Al-Ijima (Consensus). SEC. 24. Shari'ah Powers and Functions. – The powers and functions of the Shari'ah courts and the Shari'ah Public Assistance Office shall be defined by the Regional Assembly subject to the provisions of the Constitution.