Below you can find a list of math books which are free to download. Some of them I know are available on the internet after negotiations between the authors and the publishers. So, here I’d like to thank the authors for all their work writing theses books and also for their fight in favor of democratic access to knowledge!
Probability

Elementary Probability for Applications
by R. Durrett

Random Graph Dynamics
by R. Durrett

Statistical Mechanics of Lattice Systems: A Concrete Mathematical Introduction
by S. Friedli and Y. Velenik

Probability and Statistics: The Science of Uncertainty
by M. Evans and J. Rosenthal

Random Graphs and Complex Networks: Volume 1
by R. van der Hofstad

Brownian Motion
by P. Mörters and Y. Peres

Markov Chains and Mixing Times
by D. A. Levin and Y. Peres

Probability on Trees and Networks
by R. Lyons and Y. Peres

Probability: Theory and Examples
by Rick Durrett
Random Matrices

An Introduction to Random Matrices
by G. Anderson, A. Guion, O. Zeitouni

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