• Light time effect in selected semi-detached and contact binaries with observable third componentsKalv, Peep; Aas, Toomas; Harvig, Voldemar; Pustõlnik, Izold; Mars, MarioThe light-time effect in astrophysics2004 / [12] p https://www.researchgate.net/publication/234389612_Light-Time_Effect_in_Selected_Semi-detached_and_Contact_Binaries_with_Observable_Third_Components