Javadi, H., Rashed Mohasel, M., Zamani, G., Azari Nasrabad, A., & Moosavi, S. G. "The effect of plant density on yield, yield components and protein content in four grain sorghum varieties", Iranian Journal of Field Crops Research, 3, 2, 2005, 233-244. doi: 10.22067/gsc.v3i2.1307