Krashen, S. D. (1985). The input hypothesis: Issues and implications. Longman.
芝加哥风格引文Krashen, Stephen D. The Input Hypothesis: Issues and Implications. London ; New York: Longman, 1985.
MLA引文Krashen, Stephen D. The Input Hypothesis: Issues and Implications. Longman, 1985.
警告：这些引文格式不一定是100％准确.