TY  - BOOK
AU  - Hughes,G.E.
AU  - Cresswell,M.J.
TI  - A New introduction to modal logic
SN  - 0415125995
PY  - 1996///
CY  - London
PB  - Routledge
KW  - Modality (Logic)
N1  - Includes bibliographical references (p. 384-397) and index
ER  -