Cita APA (7th ed.)

Baxendale, R. W., & Baxter, R. W. (1977). A new fertile Schizaeaceous fern from Middle Pennsylvanian Iowa coal balls. University of Kansas.

Cita Chicago (17th ed.)

Baxendale, R. William, i Robert W. Baxter. A New Fertile Schizaeaceous Fern from Middle Pennsylvanian Iowa Coal Balls. Kansas: University of Kansas, 1977.

Cita MLA (9th ed.)

Baxendale, R. William, i Robert W. Baxter. A New Fertile Schizaeaceous Fern from Middle Pennsylvanian Iowa Coal Balls. University of Kansas, 1977.