Graff, H. (1976). Irumpurukku Vyavasayam. State Institute of languages.
Chicago Edition CitationGraff, Heinz. Irumpurukku Vyavasayam. Trivandrum: State Institute of languages, 1976.
Deismireacht MLAGraff, Heinz. Irumpurukku Vyavasayam. State Institute of languages, 1976.
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