Olufsen, Ole. “Ecuador. Its Ancient and Modem History, Topography and Natural Resources, Industries and Social Development, by C. Reginald Enock. With 37 Illustrations and 2 Maps. T. Fisher, Unvin London”. Geografisk Tidsskrift, bd. 25, januar 1920, https://tidsskrift.dk/geografisktidsskrift/article/view/47095.