CONNORS, James J.; VELEZ, Jonathan J. THE CONTRIBUTIONS OF E.M. TIFFANY AND THE FFA CREED TO LEADERSHIP DEVELOPMENT WITHIN THE FFA. Journal of Agricultural Education, [S. l.], v. 49, n. 2, p. 98–107, 2008. DOI: 10.5032/jae.2008.02098. Disponível em: https://jae-online.org/index.php/jae/article/view/921. Acesso em: 19 may. 2026.