In his book Quran, Hadith and Islam and his English translation of the Quran, Khalifa argued that the Quran alone is the sole source of Islamic belief and practice.[14] He claimed that the Quran had a code-system based on the number 19 which proved it's divinity. He was assassinated by Sunni traditionalists on January 31, 1990. Samina Ali (born at an unknown date in the late 20th century), Indian-American author and activist.