Polity
PM Bakshi, DD Basu, Bare Acts, Our Political System (Subash Kashyap), Our Parliament (Subhash Kashyap), Indian Polity (Laxmikant), Public Administration (Laxmikant), Indian Constitution at work : NCERT (XI), Spectrum’s Constitution India and Indian Polity, Indian Polity (Kalpana Rajaram).
Geography
NCERTS (6th to 12th), Environmental Geography (Savindra Singh), Geography of Resources & Environment (Malkit Singh), Geography of India & World (Surender Singh), India Comprehensive Geography: Khullar, Geography Work Book: S K Manocha, Geography through Maps: K Siddartha, Human Geography: Majid Hussain, Economic Geography (P Roy), Human & Economic Geography (Goh Cheng Leong & Gillian C. Morgan), Certificate Physical and Economic Geography (Goh Cheng Leong), Geography (Naradeshar Prasad), World Regional Geography (Tikka, Bali & Sekhon), Geography-A Comprehensive Study (Mahesh Kumar Barnwal), Geography for Mains: Spectrum, Economic Geography (K Sidarth), Geography of India (Majid Hussain), Social Science: Resources & Development: NCERT (VIII), Contemporary India: NCERT (IX).
Science
TMH (Ashok Kumar Singh), Kalpana Rajaram (Spectrum), NCERTS (8th-12th).
Economy
Mishra Puri, Dutt Sundaram, Economic Survey, All reports of the Govt. of India related to finance, Economic Times, Business Line, Yojna, Kurukhestra, Pratiyogita Darpan, The Gazetteer of India (Economic Structure & Activities) Latest Volume.
History
Bipin Chandra, NCERT (6th to 12th), Brief History of Modern India: Spectrum, Freedom Struggle: Bipin Chandra, Amales Tripathi & Barun De, Modern India (Sarkar), Temples of North India (Krishna Dev), Temples of South India (K R Srinivasan), Facets of Indian Culture (Kalpana Rajaram).
Current Affairs
The Hindu Newspaper (May-April), News & Events Magazine, Manorama Year Book, Chronicle, Economic Survey, India Year Book, And LOTS OF WORK FROM INTERNET & more....
Please Note: this is not the exhaustive list as there are many more books from where the references have been taken for preparing these notes. The books mentioned above have been covered to a large extent.