00446nam a2200145 a 450000500170000000800410001704100080005808200100006610000220007624500510009826400520014930000170020149000440021865000380026220260717091122.0260717s1972    ii            000 0 eng d  aeng04a511.31 aCrossley, John N.10aWhat is mathematical logic?cCrossley, John N. 1aOxford :bOxford University Press,c1972, 1979.  a82 p. : ill;0 aOxford paperbacks university series, 60 4aLogic, Symbolic and mathematical.