Wittgren, H. (1988). Removal of wastewater nitrogen in a wetland filter. Universitetet i Linköping.
Cita Chicago Style (17a ed.)Wittgren, Hans-Bertil. Removal of Wastewater Nitrogen in a Wetland Filter. Linköping, Sweden: Universitetet i Linköping, 1988.
Cita MLA (8a ed.)Wittgren, Hans-Bertil. Removal of Wastewater Nitrogen in a Wetland Filter. Universitetet i Linköping, 1988.
Precaución: Estas citas no son 100% exactas.