University of Illinois (Urbana-Champaign campus). Elementary-School Science Project & University of Illinois (Urbana-Champaign campus). Elementary-School Science Project. (1962). Astronomy (Rev. ed.). University of Illinois, Elementary School Science Project.
Trích dẫn kiểu Chicago (xuất bản lần thứ 7)University of Illinois (Urbana-Champaign campus). Elementary-School Science Project và University of Illinois (Urbana-Champaign campus). Elementary-School Science Project. Astronomy. Rev. ed. Urbana, Ill.: University of Illinois, Elementary School Science Project, 1962.
Trích dẫn kiểu MLA (xuất bản lần thứ 8)University of Illinois (Urbana-Champaign campus). Elementary-School Science Project và University of Illinois (Urbana-Champaign campus). Elementary-School Science Project. Astronomy. Rev. ed. University of Illinois, Elementary School Science Project, 1962.