This research has made use of the Jean-Marie Mariotti Center \texttt{LITpro} service co-developped by CRAL, IPAG and LAGRANGE. \footnote{LITpro software available at http://www.jmmc.fr/litpro} @INPROCEEDINGS{2008SPIE.7013E..44T, author = {{Tallon-Bosc}, I. and {Tallon}, M. and {Thi{\'e}baut}, E. and {B{\'e}chet}, C. and {Mella}, G. and {Lafrasse}, S. and {Chesneau}, O. and {Domiciano de Souza}, A. and {Duvert}, G. and {Mourard}, D. and {Petrov}, R. and {Vannier}, M.}, title = "{LITpro: a model fitting software for optical interferometry}", booktitle = {Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series}, year = 2008, series = {Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series}, volume = 7013, month = jul, doi = {10.1117/12.788871}, adsurl = {http://cdsads.u-strasbg.fr/abs/2008SPIE.7013E..44T}, adsnote = {Provided by the SAO/NASA Astrophysics Data System} }