Singh, A. K. (2013). Science & Technology for civil services examinations. Tata Mc Graw Hill.
Chicago Style aipamenaSingh, Ashok Kumar. Science & Technology for Civil Services Examinations. New Delhi: Tata Mc Graw Hill, 2013.
MLA aipamenaSingh, Ashok Kumar. Science & Technology for Civil Services Examinations. Tata Mc Graw Hill, 2013.
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