Riemannian Geometry, Manfredo Perdigao Do Carmo (Required text),
A Comprehensive Introduction to Differential Geometry, Michael Spivak,
Metric Spaces of Non-Positive Curvature, Martin R. Bridson and André Haefliger,
Foundations of Differentiable Manifolds and Lie Groups, Frank Warner.
Problem set 2 (revised with some typos fixed).
corrected sectional curvature of SO(3) (lecture 14, p.65),
corrected solution to Ricci flow on Einstein manifold (lecture 15, p.67).