Test marketing /
Sittenfeld, Hans.
Test marketing / [by] Hans Sittenfeld ; translated by E.L. Dellow. - London : Business Publications, [c1967]. - 123 p.
Test marketing.
Test marketing / [by] Hans Sittenfeld ; translated by E.L. Dellow. - London : Business Publications, [c1967]. - 123 p.
Test marketing.