Understanding the Strategic Actor Diagram: an Exercise of Meta Modeling. - Julio César Sampaio do Prado Leite; Vera Werneck; Antônio de Pádua Albuquerque Oliveira; Claudia Cappelli; Ana Luiza A. Cerqueira; Herbet de Souza Cunha; Bruno González-Baixauli (WER, 2007)