D Duncan, . M. (1984). The desing of ventilated improved pit latrines.
Cita Chicago Style (17a ed.)D Duncan, Mara. The Desing of Ventilated Improved Pit Latrines. Washington, DC : Technology Advisory Group, World Bank, 1984.
Cita MLA (9a ed.)D Duncan, Mara. The Desing of Ventilated Improved Pit Latrines. 1984.
警告：这些引文格式不一定是100％准确.