Iba, Y.; Sano, S. -I.; Mutterlose, J.; Kondo, Y. (2012). "Belemnites originated in the Triassic—A new look at an old group". Geology. 40 (10): 911–914. Bibcode:2012Geo....40..911I. doi:10.1130/G33402.1.
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Iba, Y.; Sano, S. -I.; Mutterlose, J.; Kondo, Y. (2012). "Belemnites originated in the Triassic—A new look at an old group". Geology. 40 (10): 911–914. Bibcode:2012Geo....40..911I. doi:10.1130/G33402.1.