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Leighton, Lindsey R. (2009). „Taxon Characteristics That Promote Survivorship Through the Permian-Triassic Interval: Transition from the Paleozoic to the Mesozoic Brachiopod Fauna”. Paleobiology. 34: 65—79. S2CID86843206. doi:10.1666/06082.1.
Leighton, Lindsey R. (2009). „Taxon Characteristics That Promote Survivorship Through the Permian-Triassic Interval: Transition from the Paleozoic to the Mesozoic Brachiopod Fauna”. Paleobiology. 34: 65—79. S2CID86843206. doi:10.1666/06082.1.