Ludvigsen, R. (1982). Upper Cambrian and Lower Ordovician trilobite biostratigraphy of the Rabbitkettle Formation, western District of Mackenzie. Royal Ontario Museum.
芝加哥风格引文Ludvigsen, Rolf. Upper Cambrian and Lower Ordovician Trilobite Biostratigraphy of the Rabbitkettle Formation, Western District of Mackenzie. Toronto, Canada: Royal Ontario Museum, 1982.
MLA引文Ludvigsen, Rolf. Upper Cambrian and Lower Ordovician Trilobite Biostratigraphy of the Rabbitkettle Formation, Western District of Mackenzie. Royal Ontario Museum, 1982.
警告：这些引文格式不一定是100％准确.