TY  - BOOK
AU  - Du Plooy,Gertruida M.
TI  - Communication research : : techniques, methods and applications
SN  - 0702156418
AV  - P91.3 .D8 
PY  - 2002///
CY  - Cape Town
PB  - Juta
KW  - Communication--Research
N1  - Includes bibliographical references (p. 173-177)
ER  -