Helander, C. (2002). Farming system research: An approach to developing of sustainable farming systems and the role of white clover as a component in nitrogen management.
Chicago-referens (17:e uppl.)Helander, Carl-Anders. Farming System Research: An Approach to Developing of Sustainable Farming Systems and the Role of White Clover as a Component in Nitrogen Management. 2002.
MLA-referens (8:e uppl.)Helander, Carl-Anders. Farming System Research: An Approach to Developing of Sustainable Farming Systems and the Role of White Clover as a Component in Nitrogen Management. 2002.
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