WILLIAMS, Heather R. Free E-Books May Increase Print Sales: A Study With Mixed Results. Evidence Based Library and Information Practice, [S. l.], v. 6, n. 1, p. 59–60, 2011. DOI: 10.18438/B8FS7C. Disponível em: https://journals.library.ualberta.ca/eblip/index.php/EBLIP/article/view/9470. Acesso em: 27 apr. 2024.