Localización:Structural, Syntactic, and Statistical Pattern Recognition: Joint IAPR International Workshops, SSPR 2004 and SPR 2004, Lisbon, Portugal, August 18-20, 2004 Proceedings / coord. por Ana Fred, Terry M. Caelli, Robert P. W. Duin , Aurélio C. Campilho, Dick de Ridder, 2004, ISBN 978-3-540-27868-9, págs. 1001-1009