1
by Edgerton, Robert B., 1931-
Published 1989
2
by Esedebe, P. Oisanwuche
Published 1982
3
Published 1990
4
by Chakrabarty, Bidyut
Published 1990
5
by SarDesai, D.R.
Published 1992
6
7
8
by Griffiths, Stephen Iwan
Published 1993