n.牙形刺，牙形石
MEI Shi - long , 1991 . Middle and Late Cambrian conodont and trilobite biostratigraphy in Wanxian, Hebei . Unpublished Ph. D thesis of Peking University.
武桂春, 2003. 鲁西地区晚寒武世牙形石. 北京大学博士研究生学位论文.
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