^ 3.03.13.2Ducati, J. R. VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system. CDS/ADC Collection of Electronic Catalogues. 2002, 2237: 0. Bibcode:2002yCat.2237....0D.
^Barbier-Brossat, M.; Petit, M.; Figon, P. Third bibliographic catalogue of stellar radial velocities (Text in French). Astronomy and Astrophysics Supplement Series. 1994, 108: 603. Bibcode:1994A&AS..108..603B.
^Hamann, W.-R.; Wessolowski, U.; Koesterke, L. Non-LTE spectral analyses of Wolf-Rayet stars: The nitrogen spectrum of the WN6 prototype HD 192163 (WR136). Astronomy and Astrophysics. 1994, 281: 184. Bibcode:1994A&A...281..184H. ISSN 0004-6361.
Bychkov, K. V.; Sitnik, T. G. Stratification of optical emission from NGC 6888 as a trace of the interaction between Wolf-Rayet stellar wind and the shell of a red supergiant. Astronomy Letters. 2006, 32 (6): 406. Bibcode:2006AstL...32..406B. S2CID 123039046. doi:10.1134/S1063773706060041.