1. M. Tanenbaum, A. J. Goss, and W. G. Pfann: Purification of Antimony and Tin by Zone Refining. AIME Trans., 1954, vol. 200, pp. 762–763; Journal of Metals, June 1954.
2. W. G. Pfann: Change in Ingot Shape During Zone Melting. AIME Trans., 1953, vol. 197, pp. 1441–1442; Journal of Metals, November 1953.