in the Decameron of Boccaccio (day ii. novel 9), is the Imogen of Shakespeare's Cymbeline. In male attire Zineura assumed the name of Sicurano da Finale, and Imogen of Fidele. Zineura's husband was Bernard Lomellin, and the villain was Ambrose. Imogen's husband was Posthumus Leonatus, and the villain Iachimo. In Shakespeare, the British king Cymbeline takes the place assigned by Boccaccio to the sultan.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894