In general, a reference is a relation between objects in which one object designates, or acts as a means by which to connect to or link to, another object. Such relations may occur in a variety of domains, including linguistics, logic, computer science, art, and scholarship. Thus, the objects to which the term reference applies may be of varying character ranging from concrete examples, such as a reference work in a library, as well as abstract objects, such as pointers in computer programming languages or symbols in language or mathematics.
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