D. M. Toraldo, M. Minelli, F. De Nuccio, and G. Nicolardi, “Chronic obstructive pulmonary disease phenotype desaturator with hypoxic vascular remodelling and pulmonary hypertension obtained by cluster analysis”, Multidiscip Respir Med, vol. 7, Nov. 2012, doi: 10.4081/mrm.2012.626.