New textbook (in German): “Spezielle und allgemeine Relativitaetstheorie fuer Bachelorstudenten”, by Reinhard Meinel

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A new textbook published by Springer-Verlag Berlin Heidelberg. Its first two parts give an elementary introduction to special and general relativity. The third part (“Ergaenzungen fuer Fortgeschrittene”) deals with mathematical methods that can be used, for example, to solve the black hole boundary value problem of the stationary and axially symmetric Einstein-Maxwell equations leading to the Kerr-Newman solution in a unique and straightforward manner.