UNICEF. (1990). Water quality assessment in terai tubewell project.
Chicago Style aipamenaUNICEF. Water Quality Assessment in Terai Tubewell Project. 1990.
MLA aipamenaUNICEF. Water Quality Assessment in Terai Tubewell Project. 1990.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.