แม่แบบ:R:ine:CIEL
Beekes, Robert S. P. (2011) Comparative Indo-European Linguistics: An Introduction, revised and corrected by Michiel de Vaan, 2nd edition, Amsterdam, Philadelphia: John Benjamins Publishing Company
Beekes, Robert S. P. (2011) Comparative Indo-European Linguistics: An Introduction, revised and corrected by Michiel de Vaan, 2nd edition, Amsterdam, Philadelphia: John Benjamins Publishing Company