G. D et al.,  "Penalized spline smoothing for delay in Pulmonary Tuberculosis diagnosis", in Proc. of the 28th Int. Workshop on Statistical Modelling, Volume II, Muggeo, V.M.R. and Capursi, V. and Boscaino, G. and Lovison, G., Ed., Palermo, 2013, pp. 621-625