F. Paternò, C. Santoro, and L. Spano. Proceedings of the 12th IFIP TC 13 International Conference on Human-Computer Interaction: Part I, page 892--905. Berlin/Heidelberg, Springer-Verlag, (2009)
R. Choquet, L. Rouan, and R. Pradel. Modeling Demographic Processes in Marked Populations, volume 3 of Environmental and Ecological Statistics, Springer Science & Business Media, NY, xxiv+1131.(2009)