Islam, a challenge to faith; studies on the Mohammedan religion and the needs and opportunities of the Mohammedan world from the standpoint of Christian missions, - Zwemer, Samuel Marinus, 1867-1952 (Student volunteer movement for foreign missions, 1907)
Appendices: A. Chronological tables of important events in history of Islam and of missions to Moslems.–B. William Gifford Palgrave's characterization of Allah.–C. Thomas Patrick Hughes' characterization of Mohammed.–D. List of missionary societies working among Moslems.–E. Select bibliography for further reference and study (pages 270-281)