E.A.E.S. multicenter prospective randomized trial comapring two-stage vs. single-stage management of patients with gallstone disease and ductal calculi. - Cuschieri,A.; Lezoche,E.; Morino,M.; Croce,E.; Lacy,A.; Toouli,J.; Faggioni,A.; Ribeiro,V.M.; Kakimowicz,J.; Visa,J.; Hanna,G.B. (Surg Endosc, 1999)