Menzel, D. H. (1953). Flying saucers. Harvard University Press.
Cita Chicago Style (17a ed.)Menzel, Donald H. Flying Saucers. Cambridge: Harvard University Press, 1953.
Cita MLA (8a ed.)Menzel, Donald H. Flying Saucers. Harvard University Press, 1953.
Precaución: Estas citas no son 100% exactas.