Question: English conductor Dale Clevenger was a member of Leopold Stokowski's American Symphony Orchestra and the Symphony of the Air directed by who?

full_context: Document 1: Dale Clevenger: Dale Clevenger (born 1940 in Chattanooga, Tennessee) was the Principal Horn of the Chicago Symphony Orchestra from 1966 until his retirement in June, 2013. Before joining the CSO, he was a member of Leopold Stokowski's American Symphony Orchestra and the Symphony of the Air directed by Alfred Wallenstein. He was also principal horn of the Kansas City Philharmonic. He currently teaches at theJacobs School of Music in Indiana University.
Document 2: Doug Haining: Doug Haining is a saxophonist/clarinetist who currently resides in Edina, Minnesota. He is a music graduate of St. Olaf College in Northfield, Minnesota, where he studied classical clarinet. He has performed professionally since 1974, backing national artists such as Steve Allen, Don Rickles, Bob Hope, and others, and Broadway shows such as West Side Story, Cats, A Chorus Line and many others. He has performed with the Minnesota Orchestra and St. Paul Chamber Orchestra. Doug also played short stints with Red Wolfe’s ‘Ellington Echoes’, and the Hall Brothers. Since 1979, Doug has been a member of the Wolverines Classic Jazz Orchestra. He is also a member of the recently formed BellaGala big band, and plays in other jazz groups in the area. Doug founded the Twin Cities Seven in 1999, and since then has been busy writing arrangements and compositions for the band's ever-growing library. Doug has performed with the band at many local venues and jazz festivals, and several regional performing venues outside the metro area. In 2010, Doug co-founded the Explosion Big Band with his musical cohort Scott Agster. In his spare time, he teaches privately and co-leads the Edina High School Jazz Ensemble I. He has two children, Trevor and Preston, both of whom are currently pursuing professional music careers.
Document 3: Chappaqua Orchestra: Founded in 1958 by Boris Koutzen and other musicians from the NBC Symphony who were residents of Chappaqua, New York and neighboring towns in Westchester County, the Chappaqua Orchestra annually presents a season of orchestral and chamber concerts. Renowned conductor Andrew Litton's first conducting directorship was with the Chappaqua Orchestra, and the orchestra has also been conducted by Norman Leyden, Wolfgang Schanzer, Jesse Levine, and James Sadewhite. The orchestra has premiered and commissioned works from composers such as Paul Creston, John Corigliano, Lowell Liebermann, Michael Jeffrey Shapiro, Emily Wong, and David Macdonald. Soloists such as Vanessa L. Williams, Ruth Laredo, Joseph Fuchs, Kikuei Ikeda, Jerome Rose, Jon Manasse, Tim Fain, and others have appeared with the orchestra. Michael Jeffrey Shapiro is currently the orchestra's Music Director and Conductor.
Document 4: Arturo Toscanini: Arturo Toscanini (] ; March 25, 1867 – January 16, 1957) was an Italian conductor. He was one of the most acclaimed musicians of the late 19th and of the 20th century, renowned for his intensity, his perfectionism, his ear for orchestral detail and sonority, and his eidetic memory. He was at various times the music director of La Scala in Milan, the Metropolitan Opera in New York, and the New York Philharmonic. Later in his career he was appointed the first music director of the NBC Symphony Orchestra (1937–54), and this led to his becoming a household name (especially in the United States) through his radio and television broadcasts and many recordings of the operatic and symphonic repertoire. Toscanini had absolute pitch.
Document 5: István Kertész (conductor): István Kertész (28 August 192916 April 1973) was an internationally acclaimed Jewish Hungarian orchestral and operatic conductor who, throughout his brief but distinguished career led many of the world's great orchestras, including the Cleveland, Chicago, Philadelphia, New York, Los Angeles, Pittsburgh, Detroit, San Francisco and Minnesota Orchestras in the United States, as well as the London Symphony, Vienna Philharmonic, Berlin Philharmonic, Royal Concertgebouw Orchestra, Israel Philharmonic, and L'Orchestre de la Suisse Romande. His orchestral repertoire numbered over 450 works from all periods, and was matched by a repertoire of some sixty operas ranging from Mozart, Verdi, Puccini and Wagner to the more contemporary Prokofiev, Bartók, Britten, Kodály, Poulenc and Janáček. Kertész was part of a rich musical tradition that produced fellow Hungarian conductors Fritz Reiner, Antal Doráti, János Ferencsik, Eugene Ormandy, George Szell, János Fürst, Ferenc Fricsay, and Sir Georg Solti.
Document 6: Leopold Stokowski: Leopold Anthony Stokowski (18 April 188213 September 1977) was an English conductor of Jewish-Polish and Irish descent. One of the leading and influential conductors of the early and mid-20th Century, he is best known for his long association with the Philadelphia Orchestra and for appearing in the film "Fantasia". He was especially noted for his free-hand conducting style that spurned the traditional baton and for obtaining a characteristically sumptuous sound from the orchestras he directed.
Document 7: Mahler Symphony No. 8 discography: The first complete recording of Gustav Mahler's Eighth Symphony was made on 9 April 1950, with Leopold Stokowski conducting the New York Philharmonic and combined New York choirs. The recording was of a live performance at the Carnegie Hall. Nearly two years earlier the Hungarian-born conductor Eugene Ormandy had recorded the "Veni Creator Spiritus" movement, with the Hollywood Bowl Orchestra in a performance at the Hollywood Bowl in July 1948. Since Stokowski's version at least 70 recordings of the symphony have been made, by many of the world's leading orchestras and singers, mostly during live performances. This number includes recordings which were for private or limited distribution and were not issued under commercial record labels.
Document 8: Fantasia (1940 film): Fantasia is a 1940 American animated film produced by Walt Disney and released by Walt Disney Productions. With story direction by Joe Grant and Dick Huemer, and production supervision by Ben Sharpsteen, it is the third Disney animated feature film. The film consists of eight animated segments set to pieces of classical music conducted by Leopold Stokowski, seven of which are performed by the Philadelphia Orchestra. Music critic and composer Deems Taylor acts as the film's Master of Ceremonies, providing a live-action introduction to each animated segment.
Document 9: Steve Sample, Sr.: Steve Sample, Sr. is a bandleader, arranger, composer and jazz educator now residing in Bellingham, Washington. For more than 30 years, Sample was a professor in the Music Department of the University of Alabama, where he directed the Jazz Ensembles and taught music theory, arranging and jazz related courses. Sample trained many notable jazz musicians during his long tenure at Alabama, including Gary Wheat, Birch Johnson, Kelley O'Neal, Chris Gordon, Mervyn Warren, Cedric Dent, Beth Gottlieb, Mart Avant, Dick Aven and Ray Reach. He is respected by his peers as one of the finest jazz educators in the United States. On September 26, 2008, Sample was inducted into the Alabama Jazz Hall of Fame for his contributions to jazz education.
Document 10: Joseph Anderer: Joseph Anderer is principal horn and a founding member of St. Luke’s Chamber Ensemble and the Orchestra of St. Luke's. He has also been a member of the Metropolitan Opera Orchestra’s horn section since 1984, serving as acting Principal Horn for season 1984-5 and has been Principal Horn since 2003-2004. Before joining the Met Orchestra, he was a frequent performer with the New York Philharmonic for fourteen seasons, and participated in many concerts, recordings and tours in the US, Europe, Asia, Australia and South America. He was also a member of the Boehm Quintette for many years, and premiered many works composed for that ensemble. As soloist, he has appeared with the Orchestra of St. Luke’s in Carnegie Hall including performing as soloist in the American premier of Benjamin Britten’s “Now Sleeps the Crimson Petal”, as well as at many festivals. He holds degrees from The Juilliard School, where he was a student of Ranier DeIntinis. Mr. Anderer is active in the recording studio, performing chamber music, operas, symphonic works, solo works, TV commercials and films along with performing in recitals with singers and other musicians. He has also appeared on albums by Dawn Upshaw, Billy Joel, Mandy Patinkin, Grover Washington, Jr., Marcus Roberts and Tony Bennett & k.d. lang. He has been the Horn Coach at the Verbier Festival for many years and is a member of the faculty at the Steinhardt School of New York University.
Document 11: Paul Hostetter: Paul Hostetter is the Ethel Foley Distinguished Chair in Orchestral Activities for the Schwob School of Music at Columbus State University, the Conductor and Artistic Advisor for the Sequitur Ensemble, and the Founder and Artistic Adviser to the Music Mondays chamber series in New York City. He has held appointments as the Director of the John J. Cali School of Music at Montclair State University where he also was the Director of Orchestral Studies/Associate Professor, the Music Director of the Colonial Symphony, the Music Director of the High Mountain Symphony, Artistic Director of the Winter Sun Music Festival, Music Director of the New Jersey Youth Symphony, and the Associate Conductor for the Broadway productions of Candide and George and Ira Gershwin's Fascinating Rhythm.
Document 12: Malcolm Sargent: Sir Harold Malcolm Watts Sargent (29 April 1895 – 3 October 1967) was an English conductor, organist and composer widely regarded as Britain's leading conductor of choral works. The musical ensembles with which he was associated included the Ballets Russes, the Huddersfield Choral Society, the Royal Choral Society, the D'Oyly Carte Opera Company, and the London Philharmonic, Hallé, Liverpool Philharmonic, BBC Symphony and Royal Philharmonic orchestras. Sargent was held in high esteem by choirs and instrumental soloists, but because of his high standards and a statement that he made in a 1936 interview disputing musicians' rights to tenure, his relationship with orchestral players was often uneasy. Despite this, he was co-founder of the London Philharmonic, was the first conductor of the Liverpool Philharmonic as a full-time ensemble, and played an important part in saving the Royal Philharmonic Orchestra from disbandment in the 1960s.
Document 13: Chester E Groth Music Company: Chester E Groth Music Company was founded in 1939 in downtown Minneapolis, Minnesota by professional musician Chester E. Groth. Prior to opening Groth Music, he was a cornetist in the United States Navy Band, and he also performed under the direction of John Philip Sousa. In addition to importing and selling musical instruments, music lessons were provided by Mr. Groth and his staff. Groth's daughter Nancy Groth-Kersten assumed ownership of the company in 1985 when it moved to Bloomington, Minnesota. In 2013, Groth Music acquired Music Products Inc. from Elmhurst, Illinois, expanding its nationwide service to school music programs. In 2014 the company acquired Eble Music Company from Iowa City, Iowa, which expanded Groth Music's printed music division.
Document 14: Rudolph Polk: Rudolph ("Rudy") Polk (25 November 1892 New York, New York – 16 June 1957 Los Angeles) was an American concert violinist based in New York City during his early years and, during his later years, a Hollywood film director, film industry executive, and artist manager for Jascha Heifetz, Vladimir Horowitz, José Iturbi, and Gregor Piatigorsky. In Hollywood, Polk was the assistant musical director to Morris Stoloff at Columbia Pictures. After World War II, Polk was musical director for Enterprise Studios.
Document 15: Leonard Bernstein: Leonard Bernstein ( ; August 25, 1918 – October 14, 1990) was an American composer, conductor, author, music lecturer, and pianist. He was among the first conductors born and educated in the US to receive worldwide acclaim. According to music critic Donal Henahan, he was "one of the most prodigiously talented and successful musicians in American history."
ground_truth: Alfred Wallenstein