APA (7e ed.) Bronvermelding

Ludvigsen, R. (1982). Upper Cambrian and Lower Ordovician trilobite biostratigraphy of the Rabbitkettle Formation, western District of Mackenzie. Royal Ontario Museum.

Chicago (17e ed.) Bronvermelding

Ludvigsen, Rolf. Upper Cambrian and Lower Ordovician Trilobite Biostratigraphy of the Rabbitkettle Formation, Western District of Mackenzie. Toronto, Canada: Royal Ontario Museum, 1982.

MLA (9e ed.) Bronvermelding

Ludvigsen, Rolf. Upper Cambrian and Lower Ordovician Trilobite Biostratigraphy of the Rabbitkettle Formation, Western District of Mackenzie. Royal Ontario Museum, 1982.