Jonker A., Lowe K., Kittlemann S., Janssen P. H., Ledgard S., Pacheco D. 2016. Methane emissions changed nonlinearly with graded substitution of alfalfa silage with corn grain in the diet of sheep and relation with rumen fermentation characteristics in vivo and in vitro. Journal of Animal Science, 94, 3464-33475 
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