basis of recordNiko, S.; Sone, M.; Leman, M. S. (2007). Two new species of orthocerid cephalopods from the Carboniferous Panching Limestone, West Malaysia. <em>Paleontological Research.</em> 11(4): 331-336., available online athttps://doi.org/10.2517/1342-8144(2007)11[331:tnsooc]2.0.co;2[details]