Teori Terbentuknya Alam Semesta, Tata Surya, dan Bumi

[11]Maskufa, op cit, hal. 30-31

[12] http://hbis.wordpress.com/2009/10/07/teori-tata-surya-dan-teori-big-bang/tata surya-2/

[13] Maskufa, op cit, hal. 31-32

[14] http://hbis.wordpress.com/2009/10/07/teori-tata-surya-dan-teori-big-bang/tata surya-2/

[15] Nathalie Fredette Claude Lefleur, penerjemah; Hendro Setyanto, Understanding The Universe, Jackues Fortin, 2006, hal. 22