El Castillo (village) (English Wikipedia)

Carlos Viscasillas (2009). "La Fortaleza de la Inmaculada Concepción de María" (PDF) (in Spanish). Managua, Nicaragua: Agencia Española de Cooperación Internacional para el Desarrollo (AECID). Archived from the original (PDF) on 2012-03-23. Retrieved 2011-04-24.

archive.org

Kirstin Olsen (1994). Chronology of women's history. Westport, Connecticut: Greenwood Press. p. 90. ISBN 0-313-28803-8. Retrieved 2011-04-23. Rafaela Herrera 1762.
Rubén Darío (2005). Ilan Stavans (ed.). Selected Writings: Rubén Dario. London: Penguin Books Ltd. p. 535. ISBN 0-14-303936-9. Retrieved 2011-04-23. Rafaela.

"Rafaela Herrera: File#201, Record#1651 (subscription required)" (in Spanish). Guatemala City, Guatemala: Archivo General de Centroamerica. 2009. Retrieved 2011-04-24.

Robert Edwin Peary (1889). "The Río San Juan de Nicaragua". Journal of the American Geographical Society of New York. 21: 57–86. doi:10.2307/196656. ISSN 1949-8535. JSTOR 196656. Retrieved 2011-04-23.
David F. Marley (2008). Wars of the Americas: a chronology of armed conflict in the Western Hemisphere, 1492 to the present. Vol. 1 (2nd ed.). Santa Barbara, California: ABC-CLIO, Inc. p. 441. ISBN 978-1-59884-100-8. Retrieved 2011-04-23.
Ephraim George Squier (1852). Nicaragua: its people, scenery, monuments, and the proposed interoceanic canal. Vol. I. London: Longman, Brown, Green and Longmans. pp. 110–1. Retrieved 2011-04-23.

Nicaraguan Institute of Municipal Development (2011). "El Castillo: Ficha municipal" (PDF) (in Spanish). Managua: Instituto Nicaragüense de Fomento Municipal. Archived from the original (PDF) on 2011-09-28. Retrieved 2011-04-23.

Robert Edwin Peary (1889). "The Río San Juan de Nicaragua". Journal of the American Geographical Society of New York. 21: 57–86. doi:10.2307/196656. ISSN 1949-8535. JSTOR 196656. Retrieved 2011-04-23.

Let's Go Travel (2011). "Lago de Nicaragua Overview – Practical Information". Cambridge, Massachusetts: Let's Go Publications, Inc. Archived from the original on 2010-12-05. Retrieved 2011-05-01.

Nicaragua Channel (2011). "El Castillo, Nicaragua". Seattle, Washington: New Media Holdings, Inc. Retrieved 2011-05-01.

"Indio Maíz Biological Reserve". Managua, Nicaragua: ViaNica.com. 2011. Retrieved 2011-04-23.

Nicaraguan Institute of Municipal Development (2011). "El Castillo: Ficha municipal" (PDF) (in Spanish). Managua: Instituto Nicaragüense de Fomento Municipal. Archived from the original (PDF) on 2011-09-28. Retrieved 2011-04-23.
Carlos Viscasillas (2009). "La Fortaleza de la Inmaculada Concepción de María" (PDF) (in Spanish). Managua, Nicaragua: Agencia Española de Cooperación Internacional para el Desarrollo (AECID). Archived from the original (PDF) on 2012-03-23. Retrieved 2011-04-24.
Let's Go Travel (2011). "Lago de Nicaragua Overview – Practical Information". Cambridge, Massachusetts: Let's Go Publications, Inc. Archived from the original on 2010-12-05. Retrieved 2011-05-01.