APA Citation

Ahlberg, P. (1981). Ptychopariid trilobites in the lower cambrian of Scandinavia. [s.l.]: [s.n.].

Chicago Style Citation

Ahlberg, Per. Ptychopariid Trilobites in the Lower Cambrian of Scandinavia. [s.l.]: [s.n.], 1981.

MLA Citation

Ahlberg, Per. Ptychopariid Trilobites in the Lower Cambrian of Scandinavia. [s.l.]: [s.n.], 1981.

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