NGC_1981
NGC_1981
Thực đơn
NGC_1981Liên quan
NGC 1981 NGC 1961 NGC 1818 NGC 1984 NGC 1817 NGC 1901 NGC 198 NGC 1910 NGC 1987 NGC 1931Tài liệu tham khảo
WikiPedia: NGC_1981 http://www.skyandtelescope.com/observing/overlooke... http://ned.ipac.caltech.edu/cgi-bin/nph-objsearch?...