Held, G. (2002). Understanding data communications (7th ed.). Addison-Wesley, ; Pearson Education.
Chicago-viite (17. p.)Held, Gilbert. Understanding Data Communications. 7th ed. Boston : New Delhi: Addison-Wesley, ; Pearson Education, 2002.
MLA-viite (8. p.)Held, Gilbert. Understanding Data Communications. 7th ed. Addison-Wesley, ; Pearson Education, 2002.
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