Berman Saul J. (2011). Not For Free: Revenue Strategies for a new world. Harvard Business Review Press.
芝加哥风格引文Berman Saul J. Not For Free: Revenue Strategies for a New World. Boston: Harvard Business Review Press, 2011.
MLA引文Berman Saul J. Not For Free: Revenue Strategies for a New World. Harvard Business Review Press, 2011.
警告：这些引文格式不一定是100％准确.