Frifelt, K. (1974). A possible Link between the Jemdet Nasr and the Umm an-Nar Graves of Oman. The Journal of Oman Studies, 1, 57-80. https://omanscience.com/ar/articles/a-possible-link-between-the-jemdet-nasr-and-the-umm-an-nar-graves-of-oman