Singh, A. K. (2008). Science and technology for civil services examinations. Tata Mc-Graw Hill.
Chicago Style aipamenaSingh, Ashok Kumar. Science and Technology for Civil Services Examinations. New Delhi: Tata Mc-Graw Hill, 2008.
MLA aipamenaSingh, Ashok Kumar. Science and Technology for Civil Services Examinations. Tata Mc-Graw Hill, 2008.
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