New entries
- What does i+1 mean?: Krashen, S. D. (1982). Principles and Practice in Second Language Acquisition. Pergamon. Chapter II. Source record or text.
- Is a silent period necessary?: Krashen, S. D. (1982). Principles and Practice in Second Language Acquisition. Pergamon. Chapters II–III. Source record or text.
- How should I use captions for comprehension?: Montero Perez, M., Van Den Noortgate, W., & Desmet, P. (2013). Captioned video for L2 listening and vocabulary learning: A meta-analysis. System, 41(3), 720–739. Source record or text.
- What can extensive reading research tell us?: Nakanishi, T. (2015). A meta-analysis of extensive reading research. TESOL Quarterly, 49(1), 6–37. First published online in 2014. Source record or text.
Existing research pages
The definition, Krashen guide, evidence guide, immersion comparison, glossary and FAQ keep their source lists with the claims they support.
Some links lead to a catalog or a reference list rather than the full cited work. See our methodology for how we treat these limits.
Cite this page
Jibber Jabber. "Sources." What Is Comprehensible Input?, updated 2026-11-09. https://whatiscomprehensibleinput.com/sources/
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