Berman Saul J. (2011). Not For Free: Revenue Strategies for a new world. Harvard Business Review Press.
Chicago-viite (17. p.)Berman Saul J. Not For Free: Revenue Strategies for a New World. Boston: Harvard Business Review Press, 2011.
MLA-viite (9. p.)Berman Saul J. Not For Free: Revenue Strategies for a New World. Harvard Business Review Press, 2011.
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