Free Math Textbooks
Analysis on Manifolds, 1991, by J R Munkres
By Xah Lee. Date:
2018-03-10
This is basics of differential geometry.
you should know calculus and linear algebra.
Analysis_on_Manifolds_Munkres_J_R_57550.pdf
Differential Geometry basics
Lecture Note on Curves and Surfaces, 2003, Chuu-Lian Terng
Lecture Note on Curves and Surfaces, 2005, Chuu-Lian Terng
A Modern Course on Curves and Surfaces, 2003, by Richard S Palais
Analysis on Manifolds, 1991, by J R Munkres