1. "A Natureza e seus Feitos", portada Translated Title: "Nature and its Facts", cover Creator / Contributor: Cristóvão, José Severino (author / autor) Date Created / Date Issued: undated / sin fecha
2. "A Natureza e seus Feitos", página 6 y 7 Translated Title: "Nature and its Facts", page 6 & 7 Creator / Contributor: Cristóvão, José Severino (author / autor) Date Created / Date Issued: undated / sin fecha
3. "O Cometa de Halley, O Sinal do Fim do Mundo", página 10 y 11 Translated Title: "Halley's Comet, or Sign of the World's End", page 10 & 11 Creator / Contributor: Moreira de Lacerda, Geraldo (author / autor) Date Created / Date Issued: 1985