Từ tiếng Mã Lai nguyên thuỷ *dua(ʔ).
ดูวา (duwa)
- hai.
- Hogan, David W. (1988) Urak Lawoi': Basic Structures And Dictionary (Pacific Linguistics. Series C-109)[1], Canberra: Pacific Linguistics, Research School of Pacific and Asian Studies, The Australian National University, →ISBN, tr. 53