He died in Belmont, Massachusetts.
https://www.nytimes.com/2017/10/15/obituaries/richard-wilbur-poet-laureate-and-pulitzer-winner-dies-at-96.html
First paragraphs:
By DANIEL LEWIS
OCT. 15, 2017
Richard Wilbur, whose meticulous, urbane poems earned him two Pulitzer Prizes and selection as the national poet laureate, died on Saturday in Belmont, Mass. He was 96.
His son Christopher confirmed his death, in a nursing home.
Across more than 60 years as an acclaimed American poet, Mr. Wilbur followed a muse who prized traditional virtuosity over self-dramatization; as a consequence he often found himself out of favor with the literary authorities who preferred the heat of artists like Sylvia Plath and Allen Ginsberg.
He received his first Pulitzer in 1957, and a National Book Award as well, for “Things of This World.” The collection included “A Baroque Wall-Fountain in the Villa Sciarra,” which the poet and critic Randall Jarrell called “one of the most marvelously beautiful, one of the most nearly perfect poems any American has written.”...
https://www.bostonglobe.com/metro/obituaries/2017/10/15/wilbur/n2ZJZF17OJGN1nHQOjUBWP/story.html
https://www.google.com/search?biw=1266&bih=810&q=richard+wilbur&oq=richard+wilbur&gs_l=psy-ab.3..0i131k1j0l4j0i10k1j0l4.135770.137688.0.137838.14.11.0.0.0.0.282.1468.0j5j3.8.0....0...1.1.64.psy-ab..6.8.1465...46j0i67k1j0i46k1.0.uUeMECOviiY
(more obits)
https://groups.google.com/forum/#!msg/rec.arts.books.childrens/qIS7wCjsMCk/_FfMN1xP2OEJ;context-place=forum/rec.arts.books.childrens
(birthday post from 2011, with excerpt from "The Disappearing Alphabet")
Lenona.