Tolong jelaskan mengenai Sumber dari Sadhu Sundar Singh

Paul Gaebler: Sadhu Sundar Singh, Leipzig 1937 (German).

Appasamy, A. J. Sundar Singh. Cambridge: Lutterworth, 1958.

Benge, Janet & Geoff Sundar Singh: Footprints Over the Mountains

Davey, Cyril J. The Story of Sadhu Sundar Singh (Chicago: Moody Press, 1963); reprinted as Sadhu Sundar Singh (Bromley: STL Books, 1980).

Francis, Dayanandan, ed. The Christian Witness of Sadhu Sundar Singh. Alresford: Christian Literature Crusade, 1989.

Stevens, Alec, Sadhu Sundar Singh (Dover, NJ: Calvary Comics, 2006).

Streeter, Burnett and A. J. Appasamy. The Sadhu: a Study in Mysticism and Practical Religion. London: Macmillan, 1921.

Thompson, Phyllis, Sadhu Sundar Singh (Carlisle: Operation Mobilisation, 1992).

Watson, Janet Lynn. The Saffron Robe. London: Hodder and Stoughton,1975.

Woodbridge, John. More Than Conquerors. Australia, 1992.

Benge, Geoff and Janet. "Sundar Singh: Footprints Over the Mountains" (Christian Heroes: Then and Now Series)

Much of the above detail was provided by this book.

Andrews, C. F. Sadhu Sundar Singh: A Personal Memoir. New York: Harper & Brothers, 1934.

Joyce Reason. The man who disappeared: Sundar Singh of India''. London: Edinburgh House Press, 1937