Resources

Secrets in Inequalities – Pham Kim Hung

Topics in Algebra and Analysis – Radmila Bulajich Manfrino, José Antonio Gómez Ortega, and Rogelio Valdez Delgado

Complex Number from A-Z

Polynomial articles – Yufei Zhao, Alex Remorov

Functional Equations – Titu Andreescu

Euclidean Geometry in Mathematical Olympiads – Evan Chen

A Beautiful Journey Through Olympiad Geometry – Stefan Lozanovski

Intermediate Counting and Probability – David Patrick (AoPS)

Problem-Solving Methods in Combinatorics – Pablo Soberon

Number Theory for Mathematical Contests – David A. Santos

Olympiad Number Theory Through Challenging Problems – Justin Stevens