Effects of Age Among Elderly Cancer Patients on Breakthrough Pain Management with Sublingual Fentanyl Tablets oleh Jordi Guitart, María Isabel Vargas, Vicente De Sanctis, Jordi Folch, Rafael Salazar, José Fuentes, Joan Coma, Julia Ferreras, Jordi Moya, Albert Tomás, Pere Estivill, Francisco Rodelas, Antonio Javier Jiménez, Almudena Sanz