TY  - BOOK
AU  - Aho Alfred V
AU  -  Ullman Jeffrey D
TI  - Theory of parsing , translation and compiling
T2  - Prentice hall series in automatic computation
U1  - P:7, L3.1-.2 
PY  - 1973///
CY  - Englewood
PB  - Cliffs Prentice-Hall      
KW  - LINGUISTICS
N1  - Appendix (1-A 4) 501-18p)
ER  -