Combinatorial Optimization: Theory and Algorithms
Bernhard Korte & Jens Vygen
Algorithms and Combinatorics (2)
Probabilistic Graphical Models: Principles and Techniques
Daphne Koller & Nir Friedman
Collection of Problems in Probability Theory
L. D. Meshalkin
Calculus
Gilbert Strang
Proofs: A Long-Form Mathematics Textbook
Jay Cummings