J K Chopra. (2013). Unique Quintessence of General Studies Paper-1 2013: Must read manual for UPSC/ State civil services preliminary examination. New Delhi.
Trích dẫn kiểu ChicagoJ K Chopra. Unique Quintessence of General Studies Paper-1 2013: Must Read Manual for UPSC/ State Civil Services Preliminary Examination. New Delhi, 2013.
Trích dẫn MLAJ K Chopra. Unique Quintessence of General Studies Paper-1 2013: Must Read Manual for UPSC/ State Civil Services Preliminary Examination. New Delhi, 2013.
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