Wittgren, H. (1988). Removal of wastewater nitrogen in a wetland filter. Universitetet i Linköping.
Chicago Style aipamenaWittgren, Hans-Bertil. Removal of Wastewater Nitrogen in a Wetland Filter. Linköping, Sweden: Universitetet i Linköping, 1988.
MLA aipamenaWittgren, Hans-Bertil. Removal of Wastewater Nitrogen in a Wetland Filter. Universitetet i Linköping, 1988.
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