Question: Which four act opera based on "El trovador" was written by the same composer as "Les vepres siciliennes?"
Context: Sapho is a 3-act opera by Charles Gounod to a libretto by Émile Augier which was premiered by the Paris Opera at the Salle Le Peletier on 16 April 1851.  It was presented only 9 times in its initial production, but was a "succès d'estime" for the young composer, with the critics praising Act 3 in particular.  It was later revived in 2-act (1858) and 4-act (1884) versions, achieving a total of 48 performances. Il trovatore (] ; Italian for "The Troubadour") is an opera in four acts by Giuseppe Verdi to an Italian libretto largely written by Salvadore Cammarano, based on the play "El trovador" (1836) by Antonio García Gutiérrez.  It was Gutiérrez's most successful play, one which Verdi scholar Julian Budden describes as "a high flown, sprawling melodrama flamboyantly defiant of the Aristotelian unities, packed with all manner of fantastic and bizarre incident." Veriano Luchetti (12 March 1939 – 23 April 2012) was an Italian tenor, whose career lasted from 1965 until the 1990s.  He sang in operas rarely recorded, such as Gerusalemme and I Vespri Siciliani, the Italian versions of Verdi French Grand operas Jérusalem and Les Vepres Siciliennes and L'africana, the Italian version of Meyerbeer French Grand opera L'Africaine . Les vêpres siciliennes ("The Sicilian Vespers") is a grand opéra in five acts by the Italian romantic composer Giuseppe Verdi set to a French libretto by Eugène Scribe and Charles Duveyrier from their work "Le duc d'Albe", which was written in 1838.  "Les vêpres" followed immediately after Verdi's three great mid-career masterpieces, "Rigoletto", "Il trovatore" and "La traviata" of 1850 to 1853 and was first performed at the Paris Opéra on 13 June 1855. Safié is a one act opera by American composer Henry Kimball Hadley.  The opera's libretto was written in English by Edward Oxenford, but its premiere, on April 4, 1909 in Mainz, Germany, was given in a German translation by Otto Neitzel.  Hadley conducted the premiere, and the title role was sung by American soprano Marguerite Lemon. Gallantry is a one act opera by composer Douglas Moore.  The work is a parody of soap opera, complete with sung commercial interruptions.  The work uses an English language libretto by Arnold Sundgaard.  The opera premiered in a double bill with Dominick Argento's "The Boor" on March 19, 1958, in New York City at the now-destroyed Brander Matthews Theater on 117th Street, between Amsterdam Avenue and Morningside Drive.  It was presented by the Columbia University School of Music with a student cast.  It has subsequently been staged by several other university opera theatre programs in the United States and Canada, including UCLA (1958, 1974, and 1994), Immaculate Heart College (1968), Goucher College (1969), the University of Michigan (1978), the University of Toronto (1988), San Diego State University (1989), Pepperdine University (1990), Wilfrid Laurier University (1992), the University of Arizona (1995), George Washington University (1999), and the University of Wisconsin (2003) among others.  The University of Southern California toured the opera to the Netherlands in 1968. Simon Boccanegra (] ) is an opera with a prologue and three acts by Giuseppe Verdi to an Italian libretto by Francesco Maria Piave, based on the play "Simón Bocanegra" (1843) by Antonio García Gutiérrez, whose play "El trovador" had been the basis for Verdi's 1853 opera, "Il trovatore". Bianca is a one act opera by American composer Henry Kimball Hadley.  The opera's libretto was an English-language adaptation of Carlo Goldoni's comedy "The Mistress of the Inn" by Grant Stewart.  Hadley finished the score in January, 1917, and entered it in a competition for the best American opera without chorus, for which William Wade Hinshaw offered a $1000 prize and a promise to produce the opera in New York City by the American Society of Singers.  It won, and was produced on October 19, 1918, at the Park Theater in Manhattan, with the composer conducting, and soprano Maggie Teyte in the title role. Madeline Lee is a one act opera, composed by John Haddock to a libretto written jointly by the composer and Michael Campbell.  It premiered at the Sydney Opera House on 8 October 2004 in an Opera Australia production directed by Michael Campbell and conducted by Tom Woods. Von heute auf morgen ("From Today to Tomorrow" or "From One Day to the Next") is a one act opera composed by Arnold Schoenberg, to a German libretto by "Max Blonda", the pseudonym of Gertrud Schoenberg, the composer's wife.  It is the composer's opus 32.
Answer: Il trovatore