Vieira, Cássio Leite (October 22, 2010). "Arquivo aberto". Ciência Hoje (in Portuguese). Archived from the original on February 2, 2014. Retrieved January 19, 2014.
Vieira, Cássio Leite (October 22, 2010). "Arquivo aberto". Ciência Hoje (in Portuguese). Archived from the original on February 2, 2014. Retrieved January 19, 2014.