00547nam 2200181 450 2205888http://id.bnportugal.gov.pt/bib/porbase/22058880-937175-72-2ISCAC_164.iso/21-09-2009/62819960311d1991 k y0pory0103 baengUSPractical UNIX securitySimson Garfinkel, Gene SpaffordSebastopolO´Reilly & Associates1993482 p.il.23 cm004.45BNporGarfinKelSimsonSpaffordGene070PTISCACRPC