Acevedo Tarazona, Alvaro, and Miguel Dario Cuadros Sanchez. 2014. “Political Activity of the ‘Vanguardia Liberal’ Newspaper During the Transit Period to the Liberal Republic in the Colombian Regional Department of Santander, 1929-1933”. Anuario De Historia Regional Y De Las Fronteras 19 (2):479-98. https://revistas.uis.edu.co/index.php/anuariohistoria/article/view/4290.