Berman, S. J. (2011). Not for free: Making money in the digital age. Boston, Mass: Harvard Business Review Press.
Παραπομπή Chicago StyleBerman, Saul Jay. Not for Free: Making Money in the Digital Age. Boston, Mass: Harvard Business Review Press, 2011.
Παραπομπή MLABerman, Saul Jay. Not for Free: Making Money in the Digital Age. Boston, Mass: Harvard Business Review Press, 2011.
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