Question: What is the date of death of Mignon Nevada's mother?
Sentence (from "Emma Nevada"): Emma Nevada (née Wixom) (7 February 1859 – 20 June 1940) was an American operatic soprano particularly known for her performances in operas by Bellini and Donizetti and the French composers Ambroise Thomas, Charles Gounod, and Léo Delibes.
Relevant evidence: Yes