Holbert, N. B. (1993). Practical marketing research: An integrated global perspective / Neil Bruce Holbert, Mark W. Speece. Prentice-Hall.
Lua i Stíl Chicago (17ú heag.)Holbert, Neil Bruce. Practical Marketing Research: An Integrated Global Perspective / Neil Bruce Holbert, Mark W. Speece. New York: Prentice-Hall, 1993.
Lua MLA (9ú heag.)Holbert, Neil Bruce. Practical Marketing Research: An Integrated Global Perspective / Neil Bruce Holbert, Mark W. Speece. Prentice-Hall, 1993.
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