==See also==*Black hole**Stellar black hole*Compact star**Exotic star***Preon star***Quark star==References====External links==*Abstract, Are Q-stars a serious threat for stellar-mass black hole candidates?, Miller J.C., Shahbaz T., Nolan L.A, 1997*Abstract, No observational proof of the black-hole event-horizon, Marek A. Abramowicz, Wlodek Kluzniak, Jean-Pierre Lasota, 2002
* Чёрная дыра* Кварковая звезда* Abstract, Are Q-stars a serious threat for stellar-mass black hole candidates?, Miller J.C., Shahbaz T., Nolan L.A, 1997* Abstract, No observational proof of the black-hole event-horizon, Marek A. Abramowicz, Wlodek Kluzniak, Jean-Pierre Lasota, 2002