00302nam a2200109 a 450000500170000002000150001708200160003210000280004824500450007626000450012130000260016620251203110046.0  a0486632822  a530.11bBER  aBergmann, Peter Gabriel  aIntroduction to the theory of relativity  aNew YorkbDover Publications, Inc.c1976  axii,307p.c23 cm P.B.