Walker, D. (1990). Customer first: A strategy for quality service. Gower.
芝加哥风格引文Walker, Denis. Customer First: A Strategy for Quality Service. Aldershot, Hants, England: Gower, 1990.
MLA引文Walker, Denis. Customer First: A Strategy for Quality Service. Gower, 1990.
警告：这些引文格式不一定是100％准确.