If you have trouble locating any of these papers please contact an author for a reprint. A few of the later G.P. Srivastava Group papers are available as on line Postscript documents.
G P Srivastava, D P Singh and G S Verma
Phys Rev B 6, 3053-3055 (1972).
G P Srivastava, D P Singh and G S Verma
Ind J Pure and Appl Phys 11, 79- (1973).
I Singh and G P Srivastava
Phys Stat Sol (b) 108, 467-473 (1981).
G P Srivastava and I Singh
Vacuum 31, 675-677 (1981).
G P Srivastava, I Singh, V Montgomery and R H Williams
J Phys C 16, 3627-3640 (1983).