Classical osteoblastoma, atypical osteoblastoma, and osteosarcoma: a comparative study based on clinical, histological, and biological parameters - Oliveira, Claudia Regina Gomes Cardim Mendes de; Mendonça, Berenice Bilharinho; Camargo, Olavo Pires de; Pinto, Emilia Modolo; Nascimento, Sergio Antonio Barbosa; Latorre, Maria do Rosário Dias de Oliveira; Zerbini, Maria Claudia Nogueira (Clinics, 2007)