Maria Luisa Cohen (1985). "Assisi: Birthplace of St. Francis: A New Conservation Park". Environmentalist. 5 (3). Kluwer: 227–229. doi:10.1007/BF02237618. ISSN0251-1088.
Maria Luisa Cohen (1985). "Assisi: Birthplace of St. Francis: A New Conservation Park". Environmentalist. 5 (3). Kluwer: 227–229. doi:10.1007/BF02237618. ISSN0251-1088.