Singh, S. (2017). General studies for civil service preliminary examinations: GS paper - 1. McGraw-Hill.
Chicago Edition CitationSingh, Surender. General Studies for Civil Service Preliminary Examinations: GS Paper - 1. New Delhi: McGraw-Hill, 2017.
Cita MLASingh, Surender. General Studies for Civil Service Preliminary Examinations: GS Paper - 1. McGraw-Hill, 2017.
Atenció: Aquestes cites poden no estar 100% correctes.