Hassan, M. S., Khair, A., Haque, M. M., Azad, A. K. and Hamid, A. (2009) “Genotypic variation in traditional rice varieties for chlorophyll content, SPAD value and nitrogen use efficiency”, Bangladesh Journal of Agricultural Research, 34(3), pp. 505–515. doi: 10.3329/bjar.v34i3.3977.