Lepper, G. H. (1919). From nebula to nebula or the dynamics of the heavens (4th ed.). Pittsburgh printing company.
Chicago-Zitierstil (17. Ausg.)Lepper, George Henry. From Nebula to Nebula or the Dynamics of the Heavens. 4th ed. Pittsburgh: Pittsburgh printing company, 1919.
MLA-Zitierstil (9. Ausg.)Lepper, George Henry. From Nebula to Nebula or the Dynamics of the Heavens. 4th ed. Pittsburgh printing company, 1919.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.