প্রাথমিক গণিতের ভিত্তি (প্রাইমারী ক্যাটাগরি) - মুনির হাসান
For Camp & International Olympiads
Algebra
Complex Numbers from A to ...Z - Dorin Andrica and Titu Andreescu
Topics in Functional Equations - Iurie Boreico, Nikolai Nikolov, Oleg Mushkarov, and Titu
Andreescu
Polynomials - Victor Prasolov
Secrets in Inequalities (volume 1) - Pham Kim Hung
Combinatorics
102 Combinatorial Problems - Book by Titu Andreescu and Zuming Feng
A Path to Combinatorics for Undergraduates - Textbook by Titu Andreescu and Zuming Feng
Combinatorics: A Problem Oriented Approach - Book by Daniel A Marcus
Generatingfunctionology - Book by Herbert Wilf
Geometry
103 Trigonometry Problems - Book by Titu Andreescu and Zuming Feng
Euclidean Geometry in Mathematical Olympiads - Evan Chen
Geometric Problems on Maxima and Minima - Luchezar N. Stoyanov, Oleg Mushkarov, and Titu
Andreescu
Geometry revisited - Harold Scott MacDonald Coxeter
Geometry Unbound - Kiran S. Kedlaya
Plane Euclidean Geometry: Theory and Problems - Christopher John Bradley and Tony Gardiner
Number Theory
250 problems in elementary number theory - Wacław Sierpiński
An Introduction to Diophantine Equations: A Problem-Based Approach - Book by Dorin Andrica
and Titu Andreescu
Number Theory Structures, Examples, and Problems - Andreescu, Titu, Andrica, Dorin
Theory of Numbers: A Text and Source Book of Problems - Andrew Adler, John E. Cloury
Problem Solving
The IMO Compendium: A Collection of Problems Suggested for The International Mathematical
Olympiads - Djukić, D., Janković, V., Matić, I., Petrović, N.