Media type: E-Article Title: Approximability of minimum certificate dispersal with tree structures Contributor: Izumi, Taisuke; Izumi, Tomoko; Ono, Hirotaka; Wada, Koichi imprint: Elsevier BV, 2015 Published in: Theoretical Computer Science Language: English DOI: 10.1016/j.tcs.2015.01.007 ISSN: 0304-3975 Keywords: General Computer Science ; Theoretical Computer Science Origination: Footnote: Access State: Open Access