Vequist. Wildlife Watching in America's National Parks. Texas A&M University Press.
Cita Chicago (17th ed.)Vequist. Wildlife Watching in America's National Parks. Texas A&M University Press.
Cita MLA (8th ed.)Vequist. Wildlife Watching in America's National Parks. Texas A&M University Press.
Atenció: Aquestes cites poden no estar 100% correctes.