TY  - GEN
AU  - FEYS, Robert, 1889-
TI  - Modal logics
AV  - BC 199 .M6 F4 
PY  - 1965///
CY  - Louvain
PB  - E. Nauwelaerts
KW  - Madality (Logic)
KW  - Logic, Symbolic and mathematical
ER  -