Thomas H. Cormen, Charles E. Leiserson, Ronald L. Rivest, Clifford Stein, Introduction to Algorithms (3rd Edition).

• Comprehensive coverage of recursion, divide-and-conquer, and algorithmic problem solving.

Steven S. Skiena, The Algorithm Design Manual.

• Practical insights and examples of recursive algorithms in real-world problems.

Wikipedia: Recursion (Computer Science)

• https://en.wikipedia.org/wiki/Recursion_(computer_science)
• Overview, examples, and applications of recursion.

NPTEL: Programming, Data Structures and Algorithms

• https://nptel.ac.in/courses/106/106/106106145/
• Video lectures and notes on recursion and algorithmic thinking.

Paul Zeitz, The Art and Craft of Problem Solving.

• Problem-solving strategies and recursive thinking.