1. 1High Temperature Technology, and I. E. Campbell , p.79 . John Wiley & Sons, Inc., New York, 1956 . 79 pp.
2. 2Metallurgy of Zirconium , pp.569 -60 . Benjamin Lustman, and Frank Kerze McGraw-Hill Book Co., Inc., New York, 1955 . 569 pp.
3. 3W. B. Blumenthal , Chemical Behavior of Zirconium , pp.159 -63 . D. Van Nostrand Co., Inc., Princeton, N. J., 1958 . 159 pp.
4. The Crystal Modifications of Zirconia