V729 Cyg

References

1. Bohannan1976
   Bohannan, Bruce & Conti, Peter S. “Spectroscopic Studies of O-Type Binaries. I. BD +40º4220: An Enigma Ripe for Resolution”: 1976, The Astrophysical Journal, Volume 204, pp. 797-803
   http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1976ApJ...204..797B&db_key=AST&high=3ee55bcf0917168

2. Leung1978
   Leung, Kam-Ching & Schneider, Donald P. “Evolved Contact Systems of Spectral Type O. III. V729 Cygni”: 1978, The Astrophysical Journal, Volume 224, pp. 565-569
   http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1978ApJ...224..565L&db_key=AST&high=3ee55bcf0917168