Stewart, W. D. P. (1975). Nitrogen fixation by free- living micro organisms. Cambridge University Press.
Chicago Style aipamenaStewart, W. D. P. Nitrogen Fixation by Free- Living Micro Organisms. London: Cambridge University Press, 1975.
MLA aipamenaStewart, W. D. P. Nitrogen Fixation by Free- Living Micro Organisms. Cambridge University Press, 1975.
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