Writing for graduate and advanced graduate students of physics, Rainich introduces the mathematics of relativity by treating the difficult parts one by one in a staged progression. He begins with the familiar inverse square law in terms of simple calculus, then introduces step by step more complicated situations, gradually bringing in more sophisticated mathematical tools. Not until the need arises does he bring in changes in fundamental concepts that characterize the theory of relativity, or refinements of the mathematical techniques. Annotation 2015 Ringgold, Inc., Portland, OR (protoview.com)