BIRKENHOLZ, Robert J. Teacher Perceptions Of Factors Associated With Expanding Vocational Agriculture Programs. Journal of Agricultural Education, [S. l.], v. 28, n. 2, p. 33–39, 1987. DOI: 10.5032/jaatea.1987.02033. Disponível em: https://jae-online.org/index.php/jae/article/view/399. Acesso em: 1 may. 2026.