all allusions are references, but are all references allusions? Many people, following the advice of language critics, like to make a distinction between alluding to something and referring to it. By this thinking, allude and allusion should apply to indirect references in which the source is not specifically identified: Well, well always have Paris, he told the travel agent, in an allusion to the movie Casablanca. By contrast, refer and reference usually imply specific mention of a source: I will refer to Hamlet for my conclusion: As Polonius says, Though this be madness, yet there is method int. In practice, many writers do not follow this distinction, but its certainly worthy of consideration.