TATA MCGRAW-HILL PUB. (1997). GENERAL STUDIES MANUAL FOR UPSC CIVIL SERVICES PRELIMINARY EXAMINATIONS (11TH.). TATA MCGRAW-HILL PUBLISHING COMPANY LIMITED.

TATA MCGRAW-HILL PUB. GENERAL STUDIES MANUAL FOR UPSC CIVIL SERVICES PRELIMINARY EXAMINATIONS. 11TH. NEW DELHI: TATA MCGRAW-HILL PUBLISHING COMPANY LIMITED, 1997.

TATA MCGRAW-HILL PUB. GENERAL STUDIES MANUAL FOR UPSC CIVIL SERVICES PRELIMINARY EXAMINATIONS. 11TH. TATA MCGRAW-HILL PUBLISHING COMPANY LIMITED, 1997.