Karlson David. (2004). Marketing Your Consulting or Professional Services. Viva Books.
芝加哥风格引文Karlson David. Marketing Your Consulting or Professional Services. New Delhi: Viva Books, 2004.
MLA引文Karlson David. Marketing Your Consulting or Professional Services. Viva Books, 2004.
警告：这些引文格式不一定是100％准确.