Gray, P. (2013). Free to learn: Why unleashing the instinct to play will make our children happier, more self-reliant, and better students for life. Basic Books.
Chicago Style (17th ed.) CitationGray, Peter. Free to Learn: Why Unleashing the Instinct to Play Will Make Our Children Happier, More Self-reliant, and Better Students for Life. New York: Basic Books, 2013.
MLA引文Gray, Peter. Free to Learn: Why Unleashing the Instinct to Play Will Make Our Children Happier, More Self-reliant, and Better Students for Life. Basic Books, 2013.
警告：這些引文格式不一定是100％准確.