Endoscopic endonasal transsphenoidal surgery in recurrent and residual pituitary adenomas: technical note. - Cappabianca,P.; Alfieri,A.; Colao,A.; Cavallo,L.M.; Fusco,M.; Peca,C.; Lombardi,G.; Divitiis,E de. (Minim Invasive Neurosurg, 2000)