BIBLIOGRAPHY AND SOURCES

http://tectonicablog.com/?p=37794

https://es.aleteia.org/2016/05/01/el-pozo-de-san-patricio-una-maravilla-de-la-ingenieria-renacentista-un-mapa-del-purgatorio/

https://www.labrujulaverde.com/2016/12/el-pozo-de-san-patricio-en-orvieto-una-insolita-obra-de-ingenieria-renacentista

https://www.expedia.mx/Pozo-De-San-Patricio-Orvieto.d6105038.Guia-Turistica

San Patrick's well