Orbitolina robusta

Bidgood, M.; Schlagintweit, F.; Simmons, M. (2024). The genus <i>Orbitolina</i> d'Orbigny, 1850 (larger benthic foraminifera) and its constituent species: Notes on identity and stratigraphic ranges. <em>Acta Palaeontologica Romaniae.</em> 20(2): 33-59.

Ellis, B. F.; Messina, A. R. (1940-2015). Catalogue of Foraminifera. <em>Micropaleontology Press, American Museum of Natural History, New York.</em>

Zhang, B. (1982). Orbitolina (foraminifera) from Xisang. Series of the Scientific Expedition to the Qinghai - Xisang Plateau. <em>Palaeontology of Xisang.</em> 4: 51-80 (in Chinese with English abstract).