TY - JOUR ID - TI - The AU - Mohammed A. Abdlhusein AU - Ahmed J. Hussein PY - 2020 VL - 10 IS - 2 SP - 258 EP - 275 JO - Journal of Education for Pure Science مجلة التربية للعلوم الصرفة SN - 20736592 AB - In this paper, we introduce two operator roles for the

ER -