Martínez, José María. “Rubén Darío’s New Unpublished and Unknown Documents: On La "Isla De Oro", the "Poema Del Otoño" and the Years of ‘Mundial’”. Anales de Literatura Hispanoamericana 44 (January 26, 2016): 185–218. https://doi.org/10.5209/rev_ALHI.2015.v44.51512.