Description based on: Anno 1, n. 10 (21 de maio de 1908).
Latest issue consulted: Anno 2, num. 93 (2 de agosto de 1909).
Microfilm. Leiden, The Netherlands : IDC Publishers, 1999. on 1 microfilm reel with other items ; 35 mm. (Latin American anarchist and labour periodicals, 1880-1940 ; reel 62).