Ray, J., & Ray, W. (1999). Sams teach yourself UNIX system administration in 21 days. Indianapolis, Ind.: SAMS.
Παραπομπή Chicago StyleRay, Joan, and William Ray. Sams Teach Yourself UNIX System Administration in 21 Days. Indianapolis, Ind.: SAMS, 1999.
Παραπομπή MLARay, Joan, and William Ray. Sams Teach Yourself UNIX System Administration in 21 Days. Indianapolis, Ind.: SAMS, 1999.
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