Singer, M. (1987). Passage to a human world. Hudson Institute.
Lua i Stíl Chicago (17ú heag.)Singer, Max. Passage to a Human World. Indianapolis, Ind.: Hudson Institute, 1987.
Lua MLA (8ú heag.)Singer, Max. Passage to a Human World. Hudson Institute, 1987.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.