Question: David Charles Abell is recognised as an authoritative interpreter of the musicals of a composer that has won how many Tony Awards?

Context paragraphs:
Les Misérables: The Dream Cast in Concert: Les Misérables: The Dream Cast in Concert (1995), also titled Les Misérables in Concert, is a concert version of the musical "Les Misérables", produced to celebrate the 10th anniversary of the West End production.  It was filmed in October 1995 at the Royal Albert Hall and released on DVD, VHS and LD in 1998 and re-released on DVD in North America in 2008.  The latest DVD presents the concert in its original 16x9 ratio.  Although filmed with HD cameras, a Blu-ray edition has not been released yet.  The 10th Anniversary cast stars Colm Wilkinson as Jean Valjean, Philip Quast as Inspector Javert, Michael Ball as Marius Pontmercy, Lea Salonga as Éponine, Judy Kuhn as Cosette, Ruthie Henshall as Fantine, Michael Maguire as Enjolras, Alun Armstrong as Thénardier, Jenny Galloway as Madame Thénardier, Adam Searles as Gavroche, Hannah Chick as Young Cosette, and several others, and was directed by John Caird.  The performers were chosen from the London, Broadway and Australian productions of the show and the Royal Philharmonic Orchestra was conducted by David Charles Abell.  It also aired on PBS part of the Great Performances series.

David Charles Abell: David Charles Abell (born 1958) is a British American orchestral conductor active in symphonic music, opera and musical theatre.  Known for his television appearances worldwide as conductor of the "Les Misérables" and Anniversary concerts, he is recognised as an authoritative interpreter of the musicals of Stephen Sondheim.

Glenn Slater: Glenn Slater (born 1968) is an American lyricist who collaborates with Alan Menken and other musical theatre composers.  He was nominated for the Tony Award for Best Original Score for the Broadway version of "The Little Mermaid" at the 62nd Tony Awards in 2008, his second Tony nomination for "Sister Act" at the 65th Tony Awards in 2011, and his third Tony nomination for "School of Rock" at the 70th Tony Awards in 2016.

Michael P. Price: (born August 5, 1938) is the longest serving artistic director of a professional theatre in the United States.  As the Executive Director of Goodspeed Musicals since 1968, he has produced more than 235 musicals, including 75 world premiers and transferred 19 productions to Broadway, including the world premieres of Shenandoah, Man of La Mancha and Annie.  His productions have won 13 Tony Awards and 33 nominations.  He has also accepted two special Tony Awards on Goodspeed's behalf.

Stephen Flaherty: Stephen Flaherty (born September 18, 1960) is an American composer of musical theatre.  He works most often in collaboration with the lyricist/bookwriter Lynn Ahrens.  They are best known for writing the Broadway musicals "Once on This Island", which was nominated for eight Tony Awards, "Seussical", which was nominated for the Grammy Award, and "Ragtime", which was nominated for twelve Tony Awards and won Best Original Score.  Flaherty was also nominated for two Academy Awards and two Golden Globe Awards with Lynn Ahrens for his songs and song score for the animated film musical "Anastasia".

Falsettos: Falsettos is a musical with a book by James Lapine and William Finn, and music and lyrics by Finn.  The musical consists of "March of the Falsettos" and "Falsettoland", the last two installments in one trio of one-act Off-Broadway musicals (the first was "In Trousers").  The story involves Marvin, his ex-wife Trina, his psychiatrist Mendel, his son Jason, his gay lover Whizzer Brown, and his neighbors Cordelia and Dr. Charlotte.  The musical premiered on Broadway in 1992 and was nominated for seven Tony Awards, of which it won Best Book of a Musical and Best Original Score.  It was revived briefly on Broadway in 2016, and the revival performance was nominated for five Tony Awards.

Guo Huaruo: Guo Huaruo (; 1904−1995) was a Chinese military strategist and lieutenant general of the People's Liberation Army.  According to Alastair Iain Johnston, Guo was until the mid-1980s "the CCP's most authoritative interpreter and annotator" of "The Art of War" by Sun Tzu, but Guo was "practically unknown in the West".

68th Tony Awards: The 68th Annual Tony Awards were held June 8, 2014, to recognize achievement in Broadway productions during the 2013–14 season.  The ceremony was held at Radio City Music Hall in New York City, and was televised live on CBS.  Hugh Jackman was the host, his fourth time hosting.  The 15 musical Tony Awards went to seven different musicals, and six plays shared the 11 play Tony Awards.

Dave Charles: Dave Charles, also known as David Charles is a British drummer, recording engineer & record producer.  He often appears under both names on the same album, e.g. Help Yourself's "The Return of Ken Whaley", where Dave Charles is credited with drums and vocals and David Charles as producer.

Stephen Sondheim: Stephen Joshua Sondheim ( ; born March 22, 1930) is an American composer and lyricist known for more than a half-century of contributions to musical theatre.  Sondheim has received an Academy Award, eight Tony Awards (more than any other composer, including a Special Tony Award for Lifetime Achievement in the Theatre), eight Grammy Awards, a Pulitzer Prize, a Laurence Olivier Award, and a 2015 Presidential Medal of Freedom.  He has been described by Frank Rich of "The New York Times" as "now the greatest and perhaps best-known artist in the American musical theater."  His best-known works as composer and lyricist include "A Funny Thing Happened on the Way to the Forum", "Company", "Follies", "A Little Night Music", "Pacific Overtures", "", "Merrily We Roll Along", "Sunday in the Park with George", "Into the Woods", "Assassins", and "Passion".  He also wrote the lyrics for "West Side Story" and "Gypsy".

Supporting paragraphs: David Charles Abell Stephen Sondheim
Answer: eight