TY  - BOOK
AU  - Wolfram, Sybil,
TI  -  Philosophical logic: an introduction 
SN  - 0415023181
U1  - 160  21
PY  - 1989///
CY  - London
PB  - Routledge
KW  - Logic
N1  - Includes bibliographical references (p. 263-269.) and index
ER  -