TY  - BOOK
AU  - Harder, Theodor.
AU  - Swokowski, Earl W.
TI  - Introduction to mathematical models in market and opinion research
U1  - 658.83 
PY  - 1969///
CY  - Dordrecht
PB  - Reidel
KW  - Mercadeo
KW  - Investigación
ER  -