Schoell, W. F. (1988). Marketing: Contemporary concepts and practices (3ª ed.). Allyn and Bacon.
Lua i Stíl Chicago (17ú heag.)Schoell, William F. Marketing: Contemporary Concepts and Practices. 3ª ed. Allyn and Bacon, 1988.
Lua MLA (9ú heag.)Schoell, William F. Marketing: Contemporary Concepts and Practices. 3ª ed. Allyn and Bacon, 1988.
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