F A Skinner. (1986). Nitrogen fixation with non legumes: The third international symposium on nitrogen fixation non legumes Helsinki, 2-8 september 1984. Helsinski: Martinus Nijhoff.
Chicago-tyylinen lähdeviittausF A Skinner. Nitrogen Fixation With Non Legumes: The Third International Symposium On Nitrogen Fixation Non Legumes Helsinki, 2-8 September 1984. Helsinski: Martinus Nijhoff, 1986.
MLA-viiteF A Skinner. Nitrogen Fixation With Non Legumes: The Third International Symposium On Nitrogen Fixation Non Legumes Helsinki, 2-8 September 1984. Helsinski: Martinus Nijhoff, 1986.
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