books.google.de - One of the clearest, most entertaining introductions to the subject ever written offers lucid explanations of not only the special and general theories of relativity, but also of the Michelson-Morley experiment, gravity, and spacetime, Mach's principle, the twin paradox, models of the universe and other...http://books.google.de/books/about/Relativity_simply_explained.html?hl=de&id=oExswkGgz64C&utm_source=gb-gplus-shareRelativity simply explained
