Question: What profession does Pyotr Ilyich Tchaikovsky and Gaetano Donizetti have in common?

Context paragraphs:
Pyotr Ilyich Tchaikovsky: Pyotr Ilyich Tchaikovsky ( ; Russian: Пётр Ильи́ч Чайко́вский ; 25 April/7 May 1840 – 25 October/6 November 1893), often anglicized as Peter Ilich Tchaikovsky, was a Russian composer of the romantic period, some of whose works are among the most popular music in the classical repertoire.  He was the first Russian composer whose music made a lasting impression internationally, bolstered by his appearances as a guest conductor in Europe and the United States.  Tchaikovsky was honored in 1884, by Emperor Alexander III, and awarded a lifetime pension.

Symphony No. 2 (Tchaikovsky): Pyotr Ilyich Tchaikovsky's Symphony No. 2 in C minor, Op. 17 was composed in 1872.  One of Tchaikovsky's joyful compositions, it was successful right from its premiere and also won the favor of the group of nationalistic Russian composers known as "The Five", led by Mily Balakirev.  Because Tchaikovsky used three Ukrainian folk songs to great effect in this work, it was nicknamed the "Little Russian" (Russian: Малороссийская , "Malorossiyskaya") by Nikolay Kashkin, a friend of the composer as well as a well-known musical critic of Moscow.  Ukraine was at that time frequently called "Little Russia".

Symphony in E flat (Tchaikovsky): Pyotr Ilyich Tchaikovsky's Symphony in E-flat, was commenced after the Symphony No. 5, and was intended initially to be the composer's next (i.e. sixth) symphony.  Tchaikovsky abandoned this work in 1892, only to reuse the first movement in the single-movement Third Piano Concerto, Op. 75, first performed and published after his death in 1895.  Two other movements were reworked for piano and orchestra by Sergei Taneyev as the "Andante and Finale", which was published as Tchaikovsky's Op.  posth.  79 in 1897.

Symphony No. 6 (Tchaikovsky): The Symphony No. 6 in B minor, Op. 74, Pathétique is Pyotr Ilyich Tchaikovsky's final completed symphony, written between February and the end of August 1893.  The composer entitled the work "The Passionate Symphony", employing a Russian word, Патетическая ("Pateticheskaya"), meaning "passionate" or "emotional", that was then mistranslated into French as "pathétique", "evoking pity", yet the mistranslation survived subsequent productions in every country but Russia.  The composer led the first performance in Saint Petersburg on 16/28 October of that year, nine days before his death.  The second performance, conducted by Eduard Nápravník, took place 21 days later, at a memorial concert on 6/18 November.  It included some minor corrections that Tchaikovsky had made after the premiere, and was thus the first performance of the work in the exact form in which it is known today.  The first performance in Moscow was on 4/16 December, conducted by Vasily Safonov.  It was the last of Tchaikovsky's compositions premiered in his lifetime; his last composition of all, the single-movement 3rd Piano Concerto, Op. 75, which was completed in October 1893, a short time before his death, received a posthumous premiere.

Gaetano Donizetti: Domenico Gaetano Maria Donizetti (] ; 29 November 1797 – 8 April 1848) was an Italian composer.  Along with Gioachino Rossini and Vincenzo Bellini, Donizetti was a leading composer of the "bel canto" opera style during the first half of the nineteenth century.  Donizetti's close association with the bel canto style was undoubtedly an influence on other composers such as Giuseppe Verdi (1813–1901).

Tchaikovsky Museum (Votkinsk): The Museum Estate of P.I. Tchaikovsky (Russian: Музей-усадьба П.И.  Чайковского ), commonly known as the Tchaikovsky Museum, is a museum in the town of Votkinsk, Udmurtia, Russia, dedicated to the composer Pyotr Ilyich Tchaikovsky, who spent his early childhood there.

Pezzo capriccioso: Pyotr Ilyich Tchaikovsky composed his Pezzo capriccioso, Op.  62, for cello and orchestra in a single week in August 1887.  Belying its title, this work is written in the somber key of B minor, the same key as the Symphony No. 6 "Pathétique".  The "Pezzo" is not capricious in a lighthearted sense.  The "capriccioso" aspect comes from Tchaikovsky's fanciful treatment of various aspects of the work's simple theme.  Despite some rapid passages and a turn to the major key, Tchaikovsky preserves the basic pulse and sober mood throughout the piece.

Swan Lake (1895): The 1917 Petipa/Ivanov/Drigo revival of Swan Lake is a famous version of the ballet "Swan Lake", (ru. " Лебединое Озеро"), (fr.  "Le Lac des Cygnes").  This is a ballet by Pyotr Ilyich Tchaikovsky based on an ancient German legend, presented in either four acts, four scenes (primarily outside Russia and Eastern Europe), three acts, four scenes (primarily in Russia and Eastern Europe) or, more rarely, in two acts, four scenes.  Originally choreographed by Julius Reisinger to the music of Pyotr Ilyich Tchaikovsky (opus 20), it was first presented as "The Lake of the Swans" by the Ballet of the Moscow Imperial Bolshoi Theatre on 20 February/4 March 1877 (Julian/Gregorian calendar dates) in Moscow, Russia.  Although the ballet is presented in many different versions, most ballet companies today base their stagings both choreographically and musically on this revival by Marius Petipa and Lev Ivanov, staged for the Imperial Ballet, first presented on 15 January/27 January 1895, at the Imperial Mariinsky Theatre in St. Petersburg, Russia instead of the original version.

Henry Zajaczkowski: Henry Zajaczkowski is a British musicologist and a specialist in the music of Pyotr Ilyich Tchaikovsky.  He has served as a contributor to "The Music Review," "The Musical Times" and the journal of the Tschaikowsky-Gesellschaft.  He has given talks on Russian music for BBC Radio 3 and has spoken publicly on Tchaikovsky at Lincoln Center in New York.  He taught music privately in London (1982-2013).  He is now in semi-retirement and lives and works in Nottinghamshire, England.  He has also worked as a eurythmy pianist at the Iona School, Nottingham, 2005-2010, and again from 2015-2016, following which he is, as of May 2016, engaged as a translator for the Tchaikovsky Research website.  He is assisting with translating the composer's correspondence into English.  His first translation, of a letter from 1878, concerns the opera "The Maid of Orleans. "

Pyotr Ilyich Tchaikovsky and The Five: In mid- to late-19th-century Russia, Pyotr Ilyich Tchaikovsky and a group of composers known as The Five had differing opinions as to whether should be composed following Western or native practices.  Tchaikovsky wanted to write professional compositions of such quality that they would stand up to Western scrutiny and thus transcend national barriers, yet remain distinctively Russian in melody, rhythm and other compositional characteristics.  The Five, made up of composers Mily Balakirev, Alexander Borodin, César Cui, Modest Mussorgsky, and Nikolai Rimsky-Korsakov, sought to produce a specifically Russian kind of art music, rather than one that imitated older European music or relied on European-style conservatory training.  While Tchaikovsky himself used folk songs in some of his works, for the most part he tried to follow Western practices of composition, especially in terms of tonality and tonal progression.  Also, unlike Tchaikovsky, none of The Five were academically trained in composition; in fact, their leader, Balakirev, considered academicism a threat to musical imagination.  Along with critic Vladimir Stasov, who supported The Five, Balakirev attacked relentlessly both the Saint Petersburg Conservatory, from which Tchaikovsky had graduated, and its founder Anton Rubinstein, orally and in print.

Supporting paragraphs: Pyotr Ilyich Tchaikovsky Gaetano Donizetti
Answer: composer