Al-Khafaf, E., and M. Al-Mutwali. “Calcareous Nannofossils Biostratigraphy of the Lower Part of Balambo Formation (Lower Cretaceous) in Azmir Anticline - Northeastern Iraq”. Iraqi National Journal of Earth Science (INJES), vol. 19, no. 1, June 2019, pp. 19-38, doi:10.33899/earth.2019.170269.