Hassin AL. Makhlof, Hassan Abd El-mawla Mohammeda , Gomoa L. Ahmed. (2019). Effect of Organic (Biochar, Compost and Chicken Manure) and Mineral Fertilization on Available NPK on Sandy Soil. Journal of Pure & Applied Sciences, 18(4). https://doi.org/10.51984/jopas.v18i4.392