Although you don't usually cite reference materials such as dictionaries and encyclopedias they can
Dictionary - This resource defines selected words and terms, confirms spelling, definition and pronunciation, explains how words are used, and helps to locate synonyms and antonyms.
Subject Dictionary - These sources focus on the vocabulary of a subject or discipline. (The Penguin dictionary of science)
Directory - This source gives contact information such as names, addresses, and telephone numbers.
Encyclopedia (General) - These sets provide summaries of information and ideas in a comprehensive manner. They are useful for providing facts and obtaining a broad survey of a topic. (The encyclopedia Americana)
Subject Encyclopedia - These sources contain articles on topics within a specific subject. (The encyclopedia of twentieth-century fiction)
QUICK TIP!...Subject encyclopedias and other reference books are good for background reading on a topic to find out what the general consensus is and what research questions might be viable.
A Dictionary of Media and Communication by 
Dictionary of Media and Communications by 
Hargrave's Communications Dictionary by 
Dictionary of Media and Communication Studies by 
Encyclopedic Dictionary of Semiotics, Media, and Communication by 
International Encyclopedia of Communications by 
Encyclopedia of Communication and Information by 
Encyclopedia of International Media and Communications by 
From Talking Drums to the Internet: an encyclopedia of communications technology by