Question: Who did Luis Gianneo teach, who became considered a chief exponent of Argentine folk music?

full_context: Document 1: Alberto Morán: Alberto Morán (born Remo Andrea Domenico Recagno, Strevi, Alessandria, Italy, 15 March 1922 – Buenos Aires, 16 August 1997) was an Argentine tango musician. His works at Osvaldo Pugliese's Orchestras were notable, including songs 'Pasional', 'San José de Flores' and 'El abrojito'. He died in 1997.
Document 2: Carlos Guastavino: Carlos Guastavino (April 5, 1912 - October 29, 2000) was one of the foremost Argentine composers of the 20th century. His production amounted to over 500 works, most of them songs for piano and voice, many still unpublished. His style was quite conservative, always tonal and lusciously romantic. His compositions were clearly influenced by Argentine folk music. His reputation was based almost entirely on his songs, and Guastavino has sometimes been called "the Schubert of the Pampas." Some of his songs, for example "Pueblito, mi pueblo", "La rosa y el sauce" ("The Rose and the Willow") and "" ("The Dove Was Wrong"), became national favorites. Unlike most other composers, at any time or place, Guastavino earned enough from his royalties and performing rights that he really had little need for other income.<ref name="BkltNI5818/20">MacDonald, Callum. Essay in booklet with the recording "Carlos Guastavino: The Complete Piano Music", Martin Jones, piano. Nimbus, NI 5818/20 (2008).</ref>
Document 3: Luis Bacalov: Luis Enríquez Bacalov (born 30 August 1933) is an Argentine-born Italian composer of film scores. Early on in his career, he composed scores for Spaghetti Western films. In the early 1970s, he collaborated with Italian progressive rock bands. Bacalov has been nominated twice for the Academy Award for Original Score, winning it in 1996 for "Il Postino". Bacalov has composed significant works for chorus and orchestra. Presently he is the artistic director of the "Orchestra della Magna Grecia" in Taranto, Italy.
Document 4: Ariel Ramírez: Ariel Ramírez (4 September 1921 – 18 February 2010) was an Argentine composer, pianist and music director. He was considered "a chief exponent of Argentine folk music" and noted for his "iconic" musical compositions.
Document 5: Franz Liszt: Franz Liszt (] ; Hungarian: "Liszt Ferencz" , in modern usage "Liszt Ferenc", ] ; October 22, 1811July 31, 1886) was a prolific 19th-century Hungarian composer, virtuoso pianist, conductor, music teacher, arranger, organist, philanthropist, author, nationalist and a Franciscan tertiary.
Document 6: Otto Luening: Otto Clarence Luening (June 15, 1900 – September 2, 1996) was a German-American composer and conductor, and an early pioneer of tape music and electronic music.
Document 7: Luis Rossi: Luis Rossi is an internationally renowned clarinetist. He performed as Principal clarinetist in symphony orchestras throughout South America for twenty years before he founded a clarinet workshop in Santiago, Chile, in 1986. Since then he has also focused on his work as a soloist and has offered master classes at institutions such as Indiana University (Bloomington, USA), Michigan State University (Lansing, USA), Ohio State University (Columbus, USA), Royal College of Music (London, England), the International Clarinet and Saxophone Connection at the New England Conservatory of Music (2002) and the Belgian Clarinet Academy (Ostend Conservatory). He has recorded four compact discs using Rossi Rosewood and African Blackwood clarinets.
Document 8: Argentine rock: Argentine rock (locally Rock nacional) is rock music composed or made by Argentine bands or artists mainly in the Spanish language. For nearly half a century it has been a major popular genre, and is regarded as part of the music tradition of Argentina alongside tango and Argentine folk music.
Document 9: List of Argentine operas: This is a list of operas by Argentine composers. Argentina's first native born opera composer was Francisco Hargreaves (1849-1900) who composed "La gatta bianca" (1875) and "Los estudiantes de Bologna" (1897), followed by Zenón Rolón (1856-1902) who composed several operas as well as operettas and zarzuelas. The works of many of the composers from this generation were first performed outside Argentina. Native Argentine opera was to develop much more with the massive European (mainly Italian) immigration in the late 19th century and even more with the opening of the Teatro Colón in 1908 where most of the 20th century operas listed here had their world premieres. Some of the first operas to treat Argentine subjects or national themes were Arturo Berutti's "Pampa" (1897) based on the life of Juan Moreira and "Yupanki" (1899) based on the life of Inca warrior Manqu Inka Yupanki. Also notable in this genre were Felipe Boero's "Tucumán" (1918) set during the Battle of Tucumán and "El matrero" (1929). Considered by many to be the quintessential Argentine opera, "El matrero" had a libretto based on gaucho folk tradition and incorporated Argentine folk melodies and a traditional gaucho dance. The Spanish playwright Federico García Lorca was also the inspiration for several Argentine operas. His plays, "La zapatera prodigiosa" and "Bodas de sangre", were the basis of operas by Juan José Castro, while Osvaldo Golijov's 2003 opera "Ainadamar" is based on events in the playwright's life.
Document 10: Leo Dan: Leopoldo Dante Tévez (born June 1, 1942), known as Leo Dan, is an Argentine composer and singer born in Villa Atamisqui, Santiago del Estero Province. He recorded more than 20 albums during his long career during the late 20th century between Argentina and Mexico. His appreciation for Mexican music led him to record with mariachis, and from there he went to international fame. His music was well received by the Mexican public since his voice was a good match to the traditional mariachi sound.
Document 11: Andrés Calamaro: Andrés Calamaro (Andrés Calamaro Masel, August 22, 1961), is an Argentine musician, composer and Latin Grammy winner. His former band "Los Rodríguez" was a major success in Spain in the 1990s. He is multi-instrumentalist and he became one of the main icons of the Argentine rock and has sold over 1.3 million copies.
Document 12: George Lynn (composer): George Lynn (1915 – March 16, 1989) was an American composer, conductor, pianist, organist, singer, and music educator. A longtime member of the American Society of Composers, Authors and Publishers, his compositional output encompasses more than 200 orchestral and choral pieces; many of which have been performed by major American symphony orchestras like the Denver Symphony, the American Symphony Orchestra under Leopold Stokowski, and the Philadelphia Orchestra. He taught on the music faculties of several prominent American colleges, notably conducting several university choirs. Throughout his life he was active as a conductor, organist, and pianist for various church and community choirs.
Document 13: Luis Gianneo: Luis Gianneo (1897–1968) was an Argentine composer, pianist and conductor. As music educator, he was the teacher of composers Ariel Ramirez, Juan Carlos Zorzi, Virtú Maragno, Pedro Ignacio Calderón and Rodolfo Arizaga, among others.
Document 14: Martha Argerich: Martha Argerich (born June 5, 1941) is an Argentine classical pianist, who is widely regarded as one of the greatest pianists of the second half of the 20th century.
Document 15: Manuel Romero: Manuel Romeo (September 21, 1891 – October 3, 1954 in Buenos Aires) was an Argentine film director, screenwriter, dramatist and score composer, and one of the influential directors in the cinema of Argentina of the classic era. He directed and wrote over films between 1931 and 1951 even composing the musical scores for several.
ground_truth: Ariel Ramírez