Bowen, Z. P. (1967). Brachiopoda of the Keyser Limestone (Silurian-Devonian) of Maryland and adjacent areas. Geological Society of America.
Chicago-viite (17. p.)Bowen, Zeddie Paul. Brachiopoda of the Keyser Limestone (Silurian-Devonian) of Maryland and Adjacent Areas. [New York]: Geological Society of America, 1967.
MLA-viite (9. p.)Bowen, Zeddie Paul. Brachiopoda of the Keyser Limestone (Silurian-Devonian) of Maryland and Adjacent Areas. Geological Society of America, 1967.
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