TY  - BOOK
AU  - Lewis, H.R.
AU  - Papadimitriou, C. H.
TI  - Elements of the theory of computattion
SN  - 0132734265
U1  - 511 
PY  - 1981///
CY  - London
PB  - Prentice-Hall
KW  - Theory of computation
ER  -