Devi, R. Leela (1986-01-01). History of Kerala (in ஆங்கிலம்). Vidyarthi Mithram Press & Book Depot. p. 218.
Menon, T. Madhava; Linguistics, International School of Dravidian (2002-01-01). A handbook of Kerala (in ஆங்கிலம்). International School of Dravidian Linguistics. p. 626. ISBN9788185692319.
Menon, T. Madhava; Linguistics, International School of Dravidian (2000-01-01). A handbook of Kerala (in ஆங்கிலம்). International School of Dravidian Linguistics. p. 120. ISBN9788185692272.
Alexander, P. C. (1946-01-01). The Dutch in Malabar (in ஆங்கிலம்). Annamalai University. p. 4.
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Menon, T. Madhava; Linguistics, International School of Dravidian (2000-01-01). A handbook of Kerala (in ஆங்கிலம்). International School of Dravidian Linguistics. p. 147. ISBN9788185692272.
Menon, T. Madhava; Linguistics, International School of Dravidian (2002-01-01). A handbook of Kerala (in ஆங்கிலம்). International School of Dravidian Linguistics. ISBN9788185692319.
Devi, R. Leela (1986-01-01). History of Kerala (in ஆங்கிலம்). Vidyarthi Mithram Press & Book Depot. p. 225.