Marcus, S. P., & Haeckel, E. (1910). What is this universe?: Christian faith versus monist dreams. Funk and Wagnalls company.
Lua i Stíl Chicago (17ú heag.)Marcus, Sigismund Philipp, agus Ernst Haeckel. What Is This Universe?: Christian Faith Versus Monist Dreams. London, New York: Funk and Wagnalls company, 1910.
Lua MLA (8ú heag.)Marcus, Sigismund Philipp, agus Ernst Haeckel. What Is This Universe?: Christian Faith Versus Monist Dreams. Funk and Wagnalls company, 1910.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.