BIBLIOGRAPHY CONTRIBUTOR Hellmut Ritter First name Hellmut Last name Ritter Bibliography entries by this contributor Al-Ashʻarī, Abū. 1963. Kitāb Maqālāt Al-Islāmīyīn Wa-Ikhtilāf Al-Muṣallīn. Ed. Hellmut Ritter. Wiesbaden.