Cita APA (7th ed.)
Lull, R. S. (1904). Fossil footprints of the Jura-Trias of North America.
Cita Chicago (17th ed.)
Lull, Richard Swann. Fossil Footprints of the Jura-Trias of North America. Boston, 1904.
Cita MLA (9th ed.)
Lull, Richard Swann. Fossil Footprints of the Jura-Trias of North America. 1904.
Atenció: Aquestes cites poden no estar 100% correctes.