TY  - BOOK
AU  - Ackermann,Robert John
TI  - Modern deductive logic: an introduction to its techniques and significance
T2  - Modern introductions to philosophy 
SN  - 0333080807
U1  - 162 
PY  - 1970///
CY  - London
PB  - Macmillan
KW  - Logic
N1  - Bibliography: p. 231-234
ER  -