Al-talb, M., Al-qusaymy, A. and Al-shabkon, A. 2007. Comparison Between Two Methods, H.S.L. and The Iteration Method to Estimate Parameter of Ridge. TANMIYAT AL-RAFIDAIN. 29, 86 (Jun. 2007), 170–179. DOI:https://doi.org/10.33899/tanra.2007.161705.