Fredrickson, B. (2009). Positivity (First edition.). Three Rivers Press.
芝加哥风格引文Fredrickson, Barbara. Positivity. First edition. New York: Three Rivers Press, 2009.
MLA引文Fredrickson, Barbara. Positivity. First edition. Three Rivers Press, 2009.
警告：这些引文格式不一定是100％准确.