TY  - BOOK
AU  - Nielsen H A
TI  - Methods of natural science :  An introduction
T2  - Prentice Hall fundamentals of logic series Mcmullian
U1  - R17, K7 (ER) 
PY  - 1967///
CY  - New Jersey 
PB  - Prentice Hall     
KW  - PHILOSOPHY
ER  -