Fernando Lang da Silveira ; Eliane Angela Veit ; Rafael Vasques Brandão https://7bd81d52-a-62cb3a1a-s-sites.googlegroups.com/site/reiecniecyt/volumen-6-nro-1-2011-1/REIEC_anio6_num1_art5.pdf?attachauth=ANoY7cqv7fgoSdZld2VANgemxJ27Q3ovfHB5KxJZxcQNIQncyVihIm02-B0_dqWf0TZbBCJQHPKX1pJoUpDcgYkQGQYLl_I7dY9YMUf1DGrTgRmiDgGWbMELPE2FwC0PubYFqS3X6iT03HMUXc4CSnAZdwLOc0Q5ybiPQDnlQf4M0JLlmJH-rXJRaI20dKn6aZT6_g9ocLPpD2feI-j26Dm4vbPDJH7onDx91hXI1IIjsHNTss6md_G24-fwaNGksyZyBtzEg28A&attredirects=0.
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