TY  - BOOK
AU  - Webb,John W.
AU  - Reis,Ronald A.
TI  - Programmable logic controllers: principles and applications 
SN  - 0136794084
PY  - 1999///
CY  - Upper Saddle River, N.J.
PB  - Prentice Hall
KW  - Programmable controllers
N1  - Includes bibliographical references (p. 435-437) and index
ER  -