Measure for Measure
(Shakespeare). The story is taken from a tale in G. Whetstone'sHeptameron, entitled Promos and Cassandra (1578). Promos is called by Shakespeare, “Lord Angelo;” and Cassandra is “Isabella.” Her brother, called by Shakespeare “Claudio,” is named Andrugio in the story. A similar story is given in Giovanni Giraldi Cinthio's third decade of stories.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894