Singh,Ashok Kumar. (2008). Science & Technology for civil services Examinations. Tata McGraw-Hill.
Chicago Style aipamenaSingh,Ashok Kumar. Science & Technology for Civil Services Examinations. New Delhi: Tata McGraw-Hill, 2008.
MLA aipamenaSingh,Ashok Kumar. Science & Technology for Civil Services Examinations. Tata McGraw-Hill, 2008.
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