Tassell, Arthur. African Mining Magazine. "Williamson – A Bright Future Ahead?". Brooke Pattrick Publications. De Beers Group official website. "De Beers Group: Tanzania". Retrieved April 18, 2005. Chopra, Jarat. "Tanganyika Diamond Presented to Princess Elizabeth," Old Africa, No. 21 (February–March 2009) 16–17. Chopra, Jarat. "Princess Margaret Hosted in Mwanza," Old Africa, No. 22 (April–May 2009) 20–22. Williamson, Dr. John Thorburn. "The Williamson Diamond Mine", pages 99-112 in "Rhodesia and East Africa", compiled and edited by F.S. Joelson, published in 1958 by East Africa and Rhodesia, London. "Dr. Williamson died shortly after writing this account, the only one which he ever wrote for publication." Diamond mines in Tanzania Surface mines in Tanzania Diatremes Volcanoes of Tanzania Pre-Holocene volcanoes 1940 establishments in Tanganyika