BARNES, R. Indirect methods for counting elephants in forest. Pachyderm, [S. l.], v. 16, n. 1, p. 24–30, 1993. DOI: 10.69649/pachyderm.v16i1.752. Disponível em: https://pachydermjournal.org/index.php/pachyderm/article/view/752. Acesso em: 24 apr. 2026.