Hopper, P. J., & Traugott, E. C. (2003). Grammaticalization (2nd ed.). Cambridge University Press.
Chicago Style aipamenaHopper, Paul J., and Elizabeth Closs Traugott. Grammaticalization. 2nd ed. Cambridge, UK, New York, NY: Cambridge University Press, 2003.
MLA aipamenaHopper, Paul J., and Elizabeth Closs Traugott. Grammaticalization. 2nd ed. Cambridge University Press, 2003.
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