Elementary Mathematics, Analysis,Lebesgue Integrals ..
- Basic Concepts of Mathematics by Elias Zakon
- Mathematical Analysis I by Elias Zakon
- Calculus by Gilbert Strang
- MEASURE THEORY Vol1 by David H. Fremlin
- MEASURE THEORY Vol2 by David H. Fremlin
- MEASURE THEORY Vol3 by David H. Fremlin
- MEASURE THEORY Vol4 by David H. Fremlin
- Real Analysis for Engineers by Erhan Cinlar, and Robert J. Vanderbei
- Measure Theory and Integration by Vitali Liskevich
- The Matrix Cookbook by Kaare Brandt Petersen
- Classical Geometry and Low-Dimensional Topology by Danny Calegari
- Basic algebra and trigonometry by Thomas Ward
- First Year Mathematics by William Chen
- Multivariable Calculus by George Cain, and James Herod
- Complex Analysis by George Cain
- Linear Algebra by Jim Hefferon
- Elementary Linear Algebra by Keith Matthews
- A First Course in Linear Algebra by Robert A. Beezer
- Complex Analysis by Douglas N. Arnold
- Set Theoretic Real Analysis by Krzysztof Ciesielski
- Expository notes in The finite reflection groups by Daniel Allcock
- Classical Geometry by Danny Calegari
- Difference Equations to Differential Equations by Dan Sloughter
- Course of linear algebra and multidimensional geometry by Ruslan Sharipov
- Examples, Lecture Notes and Specimen Exam Questions and Natural Sciences Tripos
- Calculus project by Michael Livshits
- The Octonions by John C. Baez
- Advanced Calculus by Shlomo Sternberg
- Design of Comparative Experiments by R. A. Bailey
- Math Alive by Ingrid Daubechies
Mathematical Logic and Set theory
- Mathematical Logic - an Introduction by Michal Walicki
- Set theory by Peter G. Dixon
- Mathematical Logic by Stephen G. Simpson
- Foundations of Mathematics by Stephen G. Simpson
- Model Theory by Stephen G. Simpson
- A Problem Course in Mathematical Logic by Stefan Bilaniuk
- Computability and Incompleteness by Jeremy Avigad
- Complete proofs of Gödel's Incompleteness Theorems by Byunghan Kim
- Fundamentals of Model Theory by William Weiss, and Cherie D'Mello
- Logic for Everyone by Robert A. Herrmann
Discrete Math
- Lecture Notes on Discrete Mathematics by László Lovász
