Petschelies, E. (2013) «LANGER, Erick D. Expecting Pears from an Elm Tree: Franciscan Missions on the Chiriguano Frontier in the Heart of South America, 1830 – 1949. Durham NC: Duke University Press, 2009, 375p», Revista Ñanduty, 2(2), pp. 130–132. Disponible en: https://ojs.ufgd.edu.br/nanduty/article/view/2568 (Accedido: 5 diciembre 2025).