Gary, Stuart (4 de octubre de 2012). «Astronomers discover twin black holes». ABC Science News. Australian Broadcasting Corporation. Consultado el 5 de octubre de 2012.
David, Trevor J.; Hillenbrand, Lynne A. (2015), «The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets», The Astrophysical Journal804 (2): 146, Bibcode:2015ApJ...804..146D, S2CID33401607, arXiv:1501.03154, doi:10.1088/0004-637X/804/2/146..
David, Trevor J.; Hillenbrand, Lynne A. (2015), «The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets», The Astrophysical Journal804 (2): 146, Bibcode:2015ApJ...804..146D, S2CID33401607, arXiv:1501.03154, doi:10.1088/0004-637X/804/2/146..
David, Trevor J.; Hillenbrand, Lynne A. (2015), «The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets», The Astrophysical Journal804 (2): 146, Bibcode:2015ApJ...804..146D, S2CID33401607, arXiv:1501.03154, doi:10.1088/0004-637X/804/2/146..
David, Trevor J.; Hillenbrand, Lynne A. (2015), «The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets», The Astrophysical Journal804 (2): 146, Bibcode:2015ApJ...804..146D, S2CID33401607, arXiv:1501.03154, doi:10.1088/0004-637X/804/2/146..