Book list from Source-1

* Introduction to the Constitution of India - D.D. Basu
* Indian Political Thought - V.P. Verma
* Modern Political Theory - S.P. Verma or Ashirvathan
* Political Thought Theory - J.P. Suda (4 Vols.)
* International Relations II
* Bookhive's Publication + Palmer and P + Magazines & News Papers
* Comparative Politics - Bookhive'b Publication
* Politics in India - Rajni Kothari
* Democracy in India - NCERT
* Organs of the Government - NCERT
* Modern India - NCERT
* Main Constitutions of Worls - K. R. Bombwall
* Comparative Govt. & Politics - Maheshwari.

Book list from Source-2

Prelims

Section A: 

1.(a) (b) (c) 'Political Theory',     —Eddy Ashirvatham
'Political Theory'    —O.P. Gauba
'Political Theory'     —Amal Ray, Mohit Bhattacharya.

2.(a) (b) (c) As above
   (d) 'Comparative Politics'     —R. Chilkote
Section B:
1.Political Theory    —Amal Ray & Mohit Bhattachary.

2.Introduction to Indian Constitution    —D.D. Basu

3.(a) India's Struggle for Independence    —Bipan Chandra.
   (b) Introduction to Indian constitution     —D.D. Basu.
   (c) Our Parliament    —S.C. Kashyap
   (d) Our Constitution     —S.C. Kashyap
   (e) Comparative Govt. & Politics    — V.N. Khanna
   (f) Comparative Govt. & Politics    —K.R. Bombwal

Mains

Paper I - Section A    
1.(a) A History of Political thought
—Subrata Mukherjee, Susheela Ramaswamy
   (b) A History of Political thought    —J.P. Suda
   (c) For Manu & Kautilya : Foundations of Indian Political thought
— V.R. Mehta

2.(a) Modern Political Theory    —S.P. Verma
   (b) Modern Political Theory    —Madan Gandhi

3.(a) Political Theory    —Eddy Ashirvatham
   (b) Political Theory    —J.C. Johri
   (c) Political Theory    —Ray & Bhattacharya
   (d) Political Theory    —O.P. Gauba
Paper I - Section B
1.(a) Comparative Govt. & Politics    —J.C. Johri
   (a) Comparative Govt. & Politics    —Ronald Chilkote

2.(a) Modern Indian Political Thinkers    —V.P. Verma
   (b) Foundations of Indian Political Thought    —V.R. Mehta
   (c) Indian Govt. and Politics    —A.S. Narang
   (c) Indian Govt. and Politics    —J.R. Siwach
   (c) Indian Govt and Politics    —M.P. Singh, Himanshu Roy
   (d) Politics in India    —Rajani Kothari
   (e) Govt. and Politics of India    —W.H. Morris Jones

Paper II - Section A
1.(a) Theoretical aspects of International Politics   
—Mahendra Kumar
   (b) Politics among Nations   —Morganthu
   (c) International Politics   —Schuman


Paper II - Section B

1.(a) International Politics    —Bookhives
   (b) Regular subscription of Frontline & World Focus (magazine)
Majority of Books referred for both mains and Prelims Syllabus are availabe in HIndi Medium also.