@book{UBHD-1006980, author={Ackermann, Robert John}, title={Modern deductive logic}, subtitle={an introd. to its techniques and significance}, publisher={Macmillan}, address={London}, year={1970}, pages={261 S.}, language={eng}, series={Modern introductions to philosophy}, library={PI [Signatur: <PI> 120 Ack 2]}, }