↑Chemical Bonding, Mark J. Winter, Oxford University Press, 1994, ISBN 0-19-855694-2
Bacaan tambahan
Greenwood, Norman N.; Earnshaw, A. (1997), Chemistry of the Elements (Edisi 2), Oxford: Butterworth-Heinemann, ISBN0-7506-3365-4 Pemeliharaan CS1: Banyak nama: authors list (link)