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3. Organizational Communication Anthology. Whatcom Community College: https://textbooks.whatcom.edu/cmst245/chapter/5-1/. Portuguese households: a tool for energy policy.” Management of Environmental Quality: An International Journal 26 (3): 407–422.
4. Data Communication and computer network. Tutorialspoint: https://www.tutorialspoint.com/data_communication_computer_network/data_communication_computer_network_tutorial.pdf.
5. Hekmat, S. Communication Networks, Pragsoft Corporation: http://www.pragsoft.com/books/CommNetwork.pdf.