{{cite journal | last1=Niaz | first1=A. | author2=M. Yaseen | author3=M. Shakar | author4=S. Sultana | author5=M. Ehsan | author6=A. Nazarat | year=2016 | title=MAIZE PRODUCTION AND NITROGEN USE EFFICIENCY IN RESPONSE TO NITROGEN APPLICATION WITH AND WITHOUT HUMIC ACID | journal=Journal of Animal and Plant Sciences | volume=26 | issue=6 | pages=1641-1651 | issn=1018-7081 | eissn=2309-8694 | publisher=Pakistan Agricultural Scientists Forum | url=https://thejaps.org.pk/AbstractView.aspx?mid=2016-JAPS-216}}