Holmberg, E. (1937). A study of double and multiple galaxies, together with inquiries into some general metagalactic problems: With an appendix containing a catalogue of 827 double and multiple galaxies. Published by the Observatory.
Trích dẫn kiểu Chicago (xuất bản lần thứ 7)Holmberg, Erik. A Study of Double and Multiple Galaxies, Together with Inquiries into Some General Metagalactic Problems: With an Appendix Containing a Catalogue of 827 Double and Multiple Galaxies. Lund, Sweden: Published by the Observatory, 1937.
Trích dẫn kiểu MLA (xuất bản lần thứ 8)Holmberg, Erik. A Study of Double and Multiple Galaxies, Together with Inquiries into Some General Metagalactic Problems: With an Appendix Containing a Catalogue of 827 Double and Multiple Galaxies. Published by the Observatory, 1937.
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