Sleepy Man (prior to late 2014 known as Sleepy Man Banjo Boys) is a bluegrass music band from Lebanon Township, New Jersey, United States.
 It is composed of the Mizzone brothers: Jonny (born 2002, banjo), Robbie (born ca. 1998, fiddle and vocals) and Tommy (born ca. 1997, guitar and background vocals) as well as bass player, Josh Thomas.
 The group's debut album "America's Music", was released in October 2011.
 Their second CD, "The Farthest Horizon", was released in October 2012.
 In February 2014, they released the single "Run", their first song on which one of them, Robbie, sings.
 Their third album "By My Side" was released in June 2014 with one instrumental song and five vocal songs.
 At The 14th Annual Independent Music Awards in 2015, the Sleepy Man Banjo Boys won awards in the "Instrumental" and "Americana" song categories for "Wildflower" and "Flesh & Bones".
Paul Richard Epworth (born 25 July 1974 in Bishop's Stortford, Hertfordshire) is an English music producer, musician, and songwriter.
 His production and writing credits include Adele, Rihanna, and Maxïmo Park amongst many others.
 On 12 February 2012 at the 54th Grammy Awards, Epworth won four Grammy Awards for Producer of the Year, Album of the Year (Adele's "21"), and Song of the Year and Record of the Year (for "Rolling in the Deep").
 He won the Academy Award for Best Original Song alongside Adele, for "Skyfall".
 His sister Mary Epworth is a singer and songwriter.
 He is a member of the Music Producers Guild.
 He also has a record label, Wolf Tone, whose artists include Glass Animals, Rosie Lowe and Plaitum.
 He has won 'Producer of the Year' at the BRIT Awards three times, the most recent in 2015.
 At the 59th Grammy Awards in 2017, Epworth won a Grammy for Album of the Year for his work on Adele's 25".
John Cowan Hartford (December 30, 1937 – June 4, 2001) was an American folk, country and bluegrass composer and musician known for his mastery of the fiddle and banjo, as well as for his witty lyrics, unique vocal style, and extensive knowledge of Mississippi River lore.
 His most successful song is "Gentle on My Mind" which won three Grammy Awards and was listed in "BMI's Top 100 Songs of the Century".
 Hartford performed with a variety of ensembles throughout his career, and is perhaps best known for his solo performances where he would interchange the guitar, banjo, and fiddle from song to song.
 He also invented his own shuffle tap dance move, and clogged on an amplified piece of plywood while he played and sang.
Juan Luis Guerra Seijas (born June 7, 1957), known professionally as Juan Luis Guerra, is a Dominican singer, songwriter, composer, and producer.
 He has sold over 30 million records, and has won numerous awards including 18 Latin Grammy Awards, two Grammy Awards, and two Latin Billboard Music Awards.
 Guerra won 3 Latin Grammy Awards in 2010, including Album of the Year.
 In 2012, he won the Latin Grammy Award for Producer of the Year.
"I Don't Wanna Play House" is a song written by Billy Sherrill and Glenn Sutton.
 In 1967, the song was Tammy Wynette's first number one country song as a solo artist.
 "I Don't Wanna Play House" spent three weeks at the top spot and a total of eighteen weeks on the chart.
 The recording earned Wynette the 1968 Grammy Award for Best Female Country Vocal Performance.
Tabula Rasā is a collaborative album by American banjoist Béla Fleck together with Vishwa Mohan Bhatt (playing traditional Indian slide guitar "Mohan veena") and Jie-Bing Chen, who plays the traditional Chinese two-string fiddle "Erhu".
 The unusual combination of Fleck's banjo together with these traditional instruments creates a unique sound on this album, which was nominated for the Grammy Award for Best World Music Album at the 39th Grammy Awards.
Robert Glasper (born April 6, 1978, in Houston, Texas) is an American pianist and record producer.
 He has been nominated for 6 Grammys, has won 3 Grammy Awards and is currently nominated for an Emmy Award.
 His 2012 album "Black Radio" won the Grammy Award for Best R&B Album at the 55th Grammy Awards.
 His 2014 album "Black Radio 2" won the Grammy Award for Best Traditional R&B Performance at the 56th Grammy Awards.
 The song "These Walls" from Kendrick Lamar's album "To Pimp A Butterfly" won Best Rap/Sung Collaboration at the 57th Grammy Awards, on which Glasper plays keys.
 The soundtrack for the film "Miles Ahead" won Best Soundtrack Compilation at the 58th Grammy Awards, for which Glasper was a producer.
 The song "Letter To The Free", written with Common, is nominated for an Emmy Award for Best Original Song in the Ava Duvernay documentary film "13th" (Netflix) at the 2017 Emmys.
Ray Alden (July 2, 1942 – September 19, 2009) was active in the Old Time Music community for nearly 40 years.
 He had taught at The Tennessee Banjo Institute, Augusta Folk Heritage Institute, Banjo Camp North, appeared in concerts, workshops, and on recordings.
 He was best known for his pioneering work recording traditional and second generation Appalachian banjo and fiddle players and styles, for which he received many awards, including a Grammy nomination.
 They include "Tommy And Fred - North Carolina Master Fiddle-Banjo Duets", "MountAiry USA", "The Young Fogies", and "The American Fogies".
 His publications include "Advanced Speaker Systems", "Music From Round Peak" and numerous articles and photographs.
The Crow: New Songs for the 5-String Banjo is a 2009 album by Steve Martin, featuring Dolly Parton, Vince Gill, Earl Scruggs, Tim O'Brien, Tony Trischka and Mary Black.
 It contains 15 songs and is the first album focusing on Martin as a musician.
 Martin's 1977 comedy recording "Let's Get Small", however, did feature him briefly playing the banjo during some of the comedy bits, and "The Steve Martin Brothers" devotes one side to banjo playing, including earlier renditions of some of the music presented here.
 It was first released on January 27, 2009 as an Amazon.com exclusive and then released to retail stores everywhere on May 19, 2009.
 On January 31, 2010, the album won the Grammy Award for Best Bluegrass Album at the 52nd Grammy Awards.
"Gentle on My Mind" is a song written by John Hartford, which won four 1968 Grammy Awards.
 Hartford himself won the award for Best Folk Performance and Best Country & Western Song (Songwriter).
 The other two awards Best Country & Western Solo Vocal Performance, Male and Best Country & Western Recording, went to American country music singer Glen Campbell for his version of Hartford's song.

Question: Which song that won four 1968 Grammy Awards was written by a musician known for his mastery of the fiddle and banjo?
Answer: Gentle on My Mind