APA (7th ed.) Citation

Ludvigsen, R. (1979). The Ordovician trilobite Pseudogygites Kobayashi in eastern and arctic North America. Royal Ontario Museum.

Chicago Style (17th ed.) Citation

Ludvigsen, Rolf. The Ordovician Trilobite Pseudogygites Kobayashi in Eastern and Arctic North America. Toronto, Canada: Royal Ontario Museum, 1979.

MLA (8th ed.) Citation

Ludvigsen, Rolf. The Ordovician Trilobite Pseudogygites Kobayashi in Eastern and Arctic North America. Royal Ontario Museum, 1979.

Warning: These citations may not always be 100% accurate.