TY  - BOOK
AU  - Powell, Len.S.
TI  - Communication an dlearining
SN  - 273406973
U1  - 621.38411 
PY  - 1969///
CY  - London
PB  - Sir Isaac Pitman and Sons Ltd.
KW  - Communication System
N1  - Dormitory:146266
ER  -