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"சுங்கம்". Tamil Lexicon. University of Madras & Universiti Chicago. melalui Jones, Russell (2007). Loan-Words in Indonesian and Malay. Yayasan Pustaka Obor Indonesia. m/s. 51.
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Sommerfeld, Ray M.; Anderson, Herschel M.; Brock, Horace R. (15 Ogos 1972). An Introduction to Taxation (dalam bahasa Inggeris). Forth Worth: Harcourt College Publishers. ISBN9780155463035. Unknown parameter |trans_title= ignored (bantuan)