Corsini, E. M.; Aguerri, J. A. L.; Debattista, Victor P.; Pizzella, A.; Barazza, F. D.; Jerjen, H. (27 March 2007). «The Bar Pattern Speed of Dwarf Galaxy NGC 4431». The Astrophysical Journal659 (2): L121–L124. doi:10.1086/518035. Bibcode: 2007ApJ...659L.121C.
Corsini, E. M.; Aguerri, J. A. L.; Debattista, Victor P.; Pizzella, A.; Barazza, F. D.; Jerjen, H. (27 March 2007). «The Bar Pattern Speed of Dwarf Galaxy NGC 4431». The Astrophysical Journal659 (2): L121–L124. doi:10.1086/518035. Bibcode: 2007ApJ...659L.121C.