Calculus
by
Tom M. Apostol
June 1969, John Wiley & sons
Differential and Integral Equations
by
Peter Collins
September 11, 2006, Oxford University Press, USA
Basic Training in Mathematics
by
Ramamurti Shankar
1995, Plenum Press
Principles of Mathematical Analysis
by
Walter Rudin
1976, McGraw-Hill Publishing
The Road to Reality
by
Roger Penrose
2004