Touloupakis, Georgios, Wilfried Stuflesser, Fabrizio Ferrara, Alessio Maione, Guido Antonini, and Cornelio Crippa. 2017. “Early-Stage Radiological Critical Analysis of Unsuccessful Cases Following a Four-Part Fracture Osteosynthesis of the Proximal Humerus: Focus on the ‘P’ Sign”. Acta Biomedica Atenei Parmensis 88 (2): 178-84. https://doi.org/10.23750/abm.v88i2.5295.