TY  - BOOK
AU  - Gradshtein I S
AU  - Boddington T
TI  - Direct and converse theorems: the elements of symbolic logic
U1  - 164 
PY  - 1963///
CY  - London
PB  - Pergamon Press
KW  - Logic
KW  - Mathematical logic
KW  - Symbolic
N1  - Transaled from Russian
ER  -