LANGENHEIM, R. L. Preliminary report on the stratigraphy of the Giron formation in Santander and Boyaca. Boletín de Geología, [S. l.], n. 3, p. 35–50, 1959. Disponível em: https://revistas.uis.edu.co/index.php/revistaboletindegeologia/article/view/4002. Acesso em: 19 may. 2024.