Diagnosis of pancreatic tumors by endoscopic ultrasound-guide fine-needle aspiration - Ardengh, José Celso; Lopes, César Vivian; Lima, Luiz Felipe Pereira; Oliveira, Juliano Rodrigues de; Venco, Filadélfio; Santo, Giulio Cesare; Modena, José Luiz Pimenta (World Journal of Gastroenterology, 2007)