The Action Principle and Partial Differential Equations

Einstein's Legacy: The Unity of Space and Time

Non-Euclidean Geometry

Global Nonlinear Stability of Schwarzschild Spacetime under Polarized Perturbations

Geometry: A Very Short Introduction

Geometrical Researches on the Theory of Parallels

Elliptic Integrable Systems: A Comprehensive Geometric Interpretation

Geometry by Construction: Object Creation and Problem-solving in Euclidean and Non-Euclidean Geometries

Multivariable Calculus and Differential Geometry

Tensors and Riemannian Geometry: With Applications to Differential Equations

Special Relativity and Classical Field Theory: The Theoretical Minimum