@book{44252,
	author = {Ibrahim, M. E.  and EL-Shamarka, Sh. A.},
	title = {Productivity and nitrogen accumulation and translocation of some maize genotypes as affected by different nitrogen fertilization levels},
	url = {http://nile.enal.sci.eg/EALE/2010/MJAR/3510/6/2109.pdf}
}