A free PDF write-up for his "Selected Topics in Mathematical Physics" course is available on the NPTEL Archive . đź“ť Core Syllabus Topics

He treats differential equations not as mere calculus exercises, but as descriptions of physical systems. His derivation and application of are often cited by students as the definitive resource for understanding response functions and boundary value problems. 4. Group Theory and Symmetry

The material generally follows the structure of his famous IIT Madras lectures:

Here is a breakdown of why this paper/book is considered a "classic" and why it might be interesting to you: