00386nam a2200157Ia 450000100060000000800410000602000070004704000130005408200220006710000210008924500400011026000490015030000100019954600070020965000120021668064150819s9999    xx            000 0 und d  aNA  cPK-LaUMT  aRCC 531.14bEIN-E  aEinstein, Albert  aEssays in PhysicscEinstein, Albert  aNew York, USA:bPhilosophical Library,c1950  a75 p.  aEN  aGravity