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^ Harahap, Eli Marlina (2014). Variasi Fonologi Dan Leksikon dialek Angkola Desa Sialagundi di Desa Aek Garugur Kabupaten Tapanuli Selatan. Metamorfosa Journal, 2. pp. 31–52.{{cite book}}: CS1 maint: location (link) CS1 maint: location missing publisher (link)
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