Thực đơn
NGC_18Thực đơn
NGC_18Liên quan
NGC 18 NGC 185 NGC 1851 NGC 188 NGC 1817 NGC 1808 NGC 1893 NGC 1818 NGC 189 NGC 1872Tài liệu tham khảo
WikiPedia: NGC_18 http://cseligman.com/text/atlas/ngc0.htm http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=... http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=... http://simbad.u-strasbg.fr/simbad/sim-id?Ident=Pul...