00509nam a2200169Ia 4500003000900000008004100009020001800050040001600068080001600084100002100100245008600121260004800207300001600255650004100271650001200312650001500324IN-BaIIA211028s9999    xx            000 0 eng d  a0-521-22523-X  cIIA Library  a531.51bDAV  aDavies, P. C. W. 4aThe forces of naturecP. C. W. Davies                                              aCambridgebCambridge University Pressc1979  aviii, 246p.  aAstronomy and astrophysics thesaurus  aGravity  aRelativity