Mobile communication systems 14 Cellular telephones 9 Telephone 8 Cellular telephone services industry 6 Cellular telephone systems 5 Social aspects 5 Dissertations 4 Dissertations, Academic 4 Wireless communication systems 4 Consumer satisfaction 3 Instant messaging 3 Mathematical models 3 Politeness (Linguistics) 3 Prank telephone calls 3 Telecommunication 3 Telephone, Wireless 3 Text messages (Telephone systems) 3 Attitudes 2 Cellular radio equipment industry 2 Consumers 2 Customer services 2 Personal communication service systems 2 Telephone stations 2 Telephone supplies industry 2 Antennas (Electronics) 1 Brand choice 1 Brand loyalty 1 Broadband communication systems 1 Cell phones 1 Cellular radio 1