Adnan Q. Mahdi et al. 2019. Palynofacies and Paleoenvironment investigation of the Hauterivian – Early Aptian Ratawi and Zubair formations, Balad oilfield, Central Iraq. Tikrit Journal of Pure Science. 24, 6 (Nov. 2019), 74–80. DOI:https://doi.org/10.25130/tjps.v24i6.440.