Al-Azawi , K. M., & Alarazah, A. A. (2015). INFLUENCE OF SEWAGE SLUDGE ON SOME TRACE ELEMENTS ACCUMILATION IN SOIL AND LETTUCE GROWTH AND YIELD. Diyala Agricultural Sciences Journal , 7(1), 44–54. Retrieved from https://journal.djas.uodiyala.edu.iq/index.php/dasj/article/view/1552