Answer:
Earlier words in a written work.
Explanation:
Referring words are pronouns that replace nouns that were earlier mentioned in a written work, they act as a connection or link between two or more sentences, clauses or ideas and join together all of them avoiding repetition of specific nouns. Referring words come in form of demonstrative pronouns (this, that, those, there, these) and interrogative pronouns (which, who, whom, what, whose), and increase fluency and clarity in a text.