Gottesman, S. T.; Ball, R.; Hunter, J. H.; Huntley, J. M. (1984). "High-resolution observations of the HI content of the barred spiral galaxies NGC 3992 and NGC 4731". The Astrophysical Journal. 286: 471. Bibcode:1984ApJ...286..471G. doi:10.1086/162622.
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Gottesman, S. T.; Ball, R.; Hunter, J. H.; Huntley, J. M. (1984). "High-resolution observations of the HI content of the barred spiral galaxies NGC 3992 and NGC 4731". The Astrophysical Journal. 286: 471. Bibcode:1984ApJ...286..471G. doi:10.1086/162622.