Ahmad, O. H. (2014). Humic substances and urea use in agriculture. Universiti Putra Malaysia Press.
Chicago Style (17th ed.) CitationAhmad, Osumanu Haruna. Humic Substances and Urea Use in Agriculture. Universiti Putra Malaysia Press, 2014.
MLA (9th ed.) CitationAhmad, Osumanu Haruna. Humic Substances and Urea Use in Agriculture. Universiti Putra Malaysia Press, 2014.
Warning: These citations may not always be 100% accurate.