LETTINK, H.; WALSCHOT, J.; ZITZEN, H. Methodenportretten. Levende Talen Magazine, Utrecht, Nederland, v. 78, n. 459, p. 121–123, 1991. Disponível em: https://lt-tijdschriften.nl/ojs/index.php/ltm/article/view/1439. Acesso em: 4 mei. 2024.