A remarkable and important archive of opera libretti from the collection of the 20th Century's greatest soprano. 106 libretti, from Alfano to Zanella, consisting primarily of her working copies of modern editions, though also including rare 19th century editions of operas by Bellini, Donizetti and Mayr. Eleven of the libretti for operas closely associated with Callas, contain markings in her hand, including line demarcations and underlining as well as marginalia and occasional edits. Verdi's "Ballo in Maschera" is boldly signed by Callas on the first free endpage. This remarkable collection is housed in four custom archival clamshell boxes, each 14 X 20.6 cm and lined with burgundy bugra paper. Further details upon request.