Singh, J; Bhattacharyya, J. C; Babu, G. S. D; Appakutty, M; Kuppuswamy, K; Moorthy, V; Devendran, P; Velu, C; Sivakumar, R(Astronomical Society of India, 1990-03)
Singh, J; Bhattacharyya, J. C; Babu, G. S. D; Appakutty, M; Kuppuswamy, K; Moorthy, V; Devendran, P; Velu, C; Sivakumar, R(Astronomical Society of India, 1990-03)