The document discusses reference in text and discourse. It describes types of co-reference relations such as anaphora and cataphora. Substitution is examined where expressions can be replaced in a text. Discourse reference is explored where linguistic expressions indicate entities being discussed. Referring expressions like pronouns are analyzed in discourse. Interpreting pronominal reference involves considering antecedent nominal or predicate expressions as well as new predicates attached to pronouns. Overall, the document looks at how references and language function in discourse through semantics, context and the interpretation of spoken or written language.