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NGC_53 Tham khảoThực đơn
NGC_53 Tham khảoLiên quan
Tài liệu tham khảo
WikiPedia: NGC_53 http://cseligman.com/text/atlas/ngc0a.htm http://dso-browser.com/dso/info/NGC/53 http://ned.ipac.caltech.edu/cgi-bin/objsearch?objn... http://spider.seds.org/ngc/revngcic.cgi?NGC53 http://www.unitconversion.org/length/parsecs-to-li... http://commons.wikimedia.org/wiki/Category:NGC_53 http://server1.wikisky.org/starview?object=NGC+53 http://server7.wikisky.org/starview?object_type=2&... http://www.wikisky.org/?object=NGC+53 http://www.wikisky.org/?object=NGC+53&img_source=D...