@article {28503,
	title = {Ccd Photometry and Modeling of the Overcontact Binary Systems Nn Vir and Yy CrB},
	volume = {296},
	year = {2005},
	month = {2005/04/1},
	pages = {265 - 268},
	abstract = {New ground-based BV RI CCD observations of the eclipsing binary systems NN Vir and YY CrB are analyzed and illustrated. New times of minima are given and new ephemerides are proposed. The light curves are analyzed with the Wilson-Devinney light curve synthesis code and new geometric and photometric elements are derived. These elements are used together with the available spectroscopic data to compute absolute elements. The evolutionary status of each system is studied by means of mass-radius diagrams. The systems NN Vir and YY CrB are found to be A-type and W-type W UMa systems, respectively.},
	isbn = {0004-640X},
	url = {https://ui.adsabs.harvard.edu/abs/2005Ap\&SS.296..265G},
	author = {Gazeas, K. D. and Niarchos, P. G.}
}
