1. Swanson, H.E., Gilfrich, N.T., Ugrinic, G.M.: US Natl. B. Cor. Stds. (Circ. No=539),5 24 (1955)
2. Cherin, P., Unger, P.: Acta Cryst.23 670 (1967)
3. Cooper, W.C., Westbury, R.A.: The structure of selenium. Zingaro, R.A., Cooper, W.C. (eds.), New York: Van Nostrand Reinhold 1974
4. Stuke, J.: Optical and electrical properties of selenium. Zingaro, R.A., Cooper, W.C. (eds.), New York: Van Nostrand Reinhold 1974
5. Compilation data published in: J. Phys. Chem. Ref. Data1 279 (1972)