Hart, R. D. An ecological systems conceptual framework for agricultural research and development.
Цитирование в стиле Чикаго (17-е изд.)Hart, Robert D. An Ecological Systems Conceptual Framework for Agricultural Research and Development. [Date of publication not identified].
Цитирование MLA (9-е изд.)Hart, Robert D. An Ecological Systems Conceptual Framework for Agricultural Research and Development.
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