1. Bearden J A and Burr A F 1967 NSRDS-NBS-14
2. Burns G 1964J. Chem. Phys. 41 1521
3. Carson T R 1971Progress in High Temperature Physics and Chemistry (Pergamon Press: Oxford) Vol. 4, p. 9
4. Evans R C 1966An Introduction to Crystal Chemistry (Cambridge University Press: Cambridge) p. 19
5. Kastner S O 1969J. Chem. Phys. 50 2896