Question: Ursula Gunther was a German musicologist, who specialized in the music of what Italian opera composer?

Context articles: Azio Corghi
Philip Gossett
Giuseppe Verdi
William Ashbrook
Hans Hickmann
Giuseppe Mosca
Ursula Günther
Antony Beaumont
Giacomo Puccini
Matteo Sansone (musicologist)

Azio Corghi (born 9 March 1937 in Cirié, Piedmont) is an Italian opera composer, also a teacher and musicologist.
 He was born at Cirié, in the Province of Turin, studied at the Turin and Milan conservatories and was a pupil of Bruno Bettinelli.
 In 2005 he was made a Grand Officer of the Order of Merit of the Italian Republic.
Philip Gossett (September 27, 1941 – June 12, 2017) was an American musicologist and historian, and Robert W. Reneker Distinguished Service Professor of Music at the University of Chicago.
 His lifelong interest in 19th-century Italian opera, which began with listening to the Metropolitan Opera broadcasts in his youth, led to the publication of a major book on the subject, "Divas and Scholars: Performing Italian Opera", which won the Otto Kinkeldey Award of the American Musicological Society as the best book on music of 2006.
Giuseppe Fortunino Francesco Verdi (] ; 9 or 10 October 1813 – 27 January 1901) was an Italian opera composer.
William Ashbrook (28 January 1922 – 31 March 2009) was an American musicologist, writer, journalist, and academic.
 He was perhaps best noted as a historian, researcher and popularizer of the works of Italian opera composer Gaetano Donizetti.
Hans Robert Hermann Hickmann (b. Roßlau, Germany, May 19, 1908; d. Blandford Forum, England, September 4, 1968) was an eminent German musicologist.
 He lived in Egypt and specialized in the music and organology of Ancient Egypt, and survivals thereof in Egyptian traditional music.
 He wrote about Egypt's tradition of cheironomy (as practiced in Ancient Egypt and still found in Coptic music) for the "Grove Dictionary of Music and Musicians".
Giuseppe Mosca (1772 in Naples – 1839 in Messina) was an Italian opera composer, the older brother of Luigi Mosca, also an opera composer.
 He is mainly remembered as the composer who said that Rossini copied in La pietra del paragone the "crescendo" from his opera "I pretendenti delusi".
Ursula Günther (15 June 1927 – 20 or 21 November 2006) was a German musicologist specializing in the fourteenth and early fifteenth centuries and the music of Giuseppe Verdi.
Antony Beaumont (born 27 January 1949 in London) is an English and German musicologist, writer, conductor and violinist.
 As a conductor, he has specialized in German music from the first half of the 20th century, including works by Zemlinsky, Weill, and Gurlitt.
 As a musicologist, he has published books on Busoni, Zemlinsky, and Mahler.
Giacomo Antonio Domenico Michele Secondo Maria Puccini (] ; 22 December 1858 29 November 1924) was an Italian opera composer who has been called "the greatest composer of Italian opera after Verdi".
Matteo Sansone is an Italian musicologist who specializes in the study of 19th century Italian opera.
 He received his PhD in Italian Literature from the University of Edinburgh and teaches the subject of Italian Opera at New York University in Florence and at the British Institute of Florence.
 He is the author of several publications on the topic of opera and has written several entries in the "Grove Dictionary of Music and Musicians".