ebrary, Inc, & Melark, P. G. (2012). Comets: Characteristics, composition and orbits. Nova Science Publishers.
Čikaški stil citiranja (17. izdanje)ebrary, Inc, i Peter G. Melark. Comets: Characteristics, Composition and Orbits. Hauppauge, N.Y.: Nova Science Publishers, 2012.
MLA način citiranja (9. izdanje)ebrary, Inc, i Peter G. Melark. Comets: Characteristics, Composition and Orbits. Nova Science Publishers, 2012.
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