When you cite LibOPF, please make references to:
@Manual{LibOPF, author = {Jo\~ao Paulo Papa and Celso Tetsuo Nagase Suzuki and Alexandre Xavier Falc\~ao}, title = {{LibOPF}: {A} library for the design of optimum-path forest classifiers}, year = {2014}, note = {Software version 2.1 available at \url{http://www.ic.unicamp.br/~afalcao/LibOPF}} }
@article{PapaIJIST09, author = {J. P. Papa and A. X. Falc{\~{a}}o and Celso T. N. Suzuki}, title = {Supervised Pattern Classification based on Optimum-Path Forest}, journal = {International Journal of Imaging Systems and Technology}, volume = {19}, issue = {2}, pages = {120--131}, publisher = {Wiley-Interscience}, year = {2009}, }
@article{PapaPR:12, Address = {New York, NY, USA}, Author = {Jo{\~{a}}o Paulo Papa and Alexandre Xavier Falc{\~{a}}o and Victor Hugo Costa Albuquerque and Jo{\~{a}}o Manuel Ribeiro Silva Tavares}, Journal = {Pattern Recognition}, Number = {1}, Pages = {512--520}, Publisher = {Elsevier Science Inc.}, Title = {Efficient supervised optimum-path forest classification for large datasets}, Volume = {45}, Year = {2012}}
@article{RochaIJIST09, author = {L.M. Rocha and F.A.M. Cappabianco and A.X. Falc{\~{a}}o}, title = {Data clustering as an optimum-path forest problem with applications in image analysis}, journal = {International Journal of Imaging Systems and Technology}, publisher = {Wiley Periodicals}, volume = {19}, number = {2}, pages = {50--68}, year = {2009} }