Richards, Y. (2012). Classification and Types of Geocentric Orbits. Delhi, India : University Publication : World Technologies.
Chicago-viite (17. p.)Richards, Yu. Classification and Types of Geocentric Orbits. Delhi, India : University Publication : World Technologies, 2012.
MLA-viite (9. p.)Richards, Yu. Classification and Types of Geocentric Orbits. Delhi, India : University Publication : World Technologies, 2012.
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