UX Mon: time keeping and modelling of a binary [Observed: 13 Dec 2007, 11-16, 18 Feb, 8, 13, 14 March, 1, 4, 25, 29]
Time series of this eclipsing binary system with extra variability are presented. The O-C analysis suggests the presence of a third star. The observations are modelled with BinaryMaker3 and parameters of the system are derived.

Binary systems: orbital period and mass transfer []
The equations for the relation between the orbital period change of a binary system and the mass transfer are explicited.