^"Grey, Sir George (1812–1898)". Australian Dictionary of Biography. National Centre of Biography, Australian National University. Retrieved 23 March 2016.
^Espitalier, T.J.; Day, W.A.J. (1943). The Locomotive in South Africa - A Brief History of Railway Development. Chapter I - The Period of the 4 ft. 8½ in. Gauge. South African Railways and Harbours Magazine, June 1943. pp. 437-440.
^"Grey, Sir George (1812–1898)". Australian Dictionary of Biography. National Centre of Biography, Australian National University. Retrieved 23 March 2016.
^Espitalier, T.J.; Day, W.A.J. (1943). The Locomotive in South Africa - A Brief History of Railway Development. Chapter I - The Period of the 4 ft. 8½ in. Gauge. South African Railways and Harbours Magazine, June 1943. pp. 437-440.