Wittgren, H. (1988). Removal of wastewater nitrogen in a wetland filter. Universitetet i Linköping.
Chicagoスタイル(17版)引用形式Wittgren, Hans-Bertil. Removal of Wastewater Nitrogen in a Wetland Filter. Linköping, Sweden: Universitetet i Linköping, 1988.
MLA(8版)引用形式Wittgren, Hans-Bertil. Removal of Wastewater Nitrogen in a Wetland Filter. Universitetet i Linköping, 1988.
警告: この引用は必ずしも正確ではありません.