000 003380000a22001450004500
008 140223b1980 xxu||||| |||| 00| 0 eng d
041 _aEng
080 _aR15 M0
082 _aR15 M0
100 _aChellas Brian F.
245 _aModal logic: Introduction.
260 _aCambridge
_bCUP
_c1980
650 _aModal
650 _aPhilosophy
999 _c69019
_d69019