by Ferilli, S., Basile, T.M.A., Biba, M., Di Mauro, N., Esposito, F.
Published in Fundamenta informaticae (01.01.2009)

by Ali, Bilel Ben, Masmoudi, Youssef, Dhouib, Souhail
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by Savvides, M., Abiantun, R., Heo, J., Park, S., Xie, C., Vijayakumar, B.V.K.
Published in 2006 Conference on Computer Vision and Pattern Recognition Workshop (CVPRW'06) (2006)