Question: What is the country of citizenship for the father of the River Song performer?

full_context: Document 1: Fathers and Sons (album): Fathers and Sons is the seventh studio album by American blues musician Muddy Waters, originally released as a double LP by Chess Records in August 1969.
Document 2: Dreamer (Dennis Wilson song): "Dreamer" is a song written by Dennis Wilson and his close friend Gregg Jakobson. It was released as the fifth track on Dennis Wilson's 1977 solo album "Pacific Ocean Blue". The track, as with the rest of the album, was credited as being produced by Dennis Wilson and Gregg Jakobson.
Document 3: Good Vibrations: ``Good Vibrations ''is a song composed by Brian Wilson with words by Mike Love for the American rock band the Beach Boys, of which both were members. Released on October 10, 1966, the single was an immediate critical and commercial hit, topping record charts in several countries including the US and UK. Characterized by its complex soundscapes, episodic structure, and subversions of pop music formula, it was the costliest single ever recorded at the time of its release.`` Good Vibrations'' later became widely acclaimed as one of the greatest masterpieces of rock music.
Document 4: Get Away (Bobby Brown song): "Get Away" is a song performed and co-written by Bobby Brown, issued as the third single from his album "Bobby". In 1993, the song peaked at #14 on the "Billboard" Hot 100, as well as reaching #1 on the "Billboard" dance chart.
Document 5: Classics Selected by Brian Wilson: Classics selected by Brian Wilson is a compilation of songs by The Beach Boys and released through Capitol Records in mid-2002. It was compiled by Brian Wilson himself that February. It includes a new recording of an unreleased 1970s track, "California Feelin'" not by The Beach Boys but Wilson and his live band.
Document 6: Pacific Ocean Blues: A backing track was reportedly recorded by late 1975 and was Dennis Wilson's only submission for The Beach Boys 1976 album "15 Big Ones", though it was turned down by the band. The completed version, although a hard rocker, features water sound effects. Dennis has been quoted as calling the song "my least favorite cut" on the album as he reportedly felt that the song sounded incomplete.
Document 7: The Many Moods of Murry Wilson: The Many Moods of Murry Wilson is the sole album release by Murry Wilson, the father of Brian, Carl and Dennis Wilson and uncle of Mike Love of The Beach Boys. The album was released on Capitol Records in 1967, the same record label that The Beach Boys were contracted to at the time.
Document 8: River Song (Dennis Wilson song): "River Song" is a song written by Dennis Wilson and his younger brother Carl Wilson. It served as the opening track for Dennis Wilson's 1977 debut solo album "Pacific Ocean Blue". The song was released as a single in Europe with the B-side being "Farewell My Friend". The single however, failed to chart. The track, as with the rest of the album, was credited as being produced by Dennis and his close friend Gregg Jakobson. Dennis Wilson sings the lead vocals on this and every other track on the album.
Document 9: Don't Worry Baby: ``Do n't Worry Baby ''is a song written by Brian Wilson and Roger Christian, produced by Wilson and first recorded by the American rock band The Beach Boys. The band's version, a tender ballad with falsetto lead vocal by Wilson, was first released on their 1964 album Shut Down Volume 2. It was also released as the B - side of The Beach Boys' first US number - one,`` I Get Around'', also reaching number 24 on the Billboard Hot 100 in its own right.
Document 10: Bee Gees: When it, too, failed to attract much interest, Mardin encouraged them to work within the soul music style. The brothers attempted to assemble a live stage band that could replicate their studio sound. Lead guitarist Alan Kendall had come on board in 1971 but did not have much to do until Mr. Natural. For that album, they added drummer Dennis Bryon, and they later added ex-Strawbs keyboard player Blue Weaver, completing the Bee Gees band that lasted through the late '70s. Maurice, who had previously performed on piano, guitar, harpsichord, electric piano, organ, mellotron and bass guitar, as well as mandolin and Moog synthesiser, by then confined himself to bass onstage.
Document 11: You and I (Dennis Wilson song): "You and I" is a song written by Dennis Wilson, his former wife Karen Lamm-Wilson and close friend Gregg Jakobson. It was released as the eighth track on Dennis Wilson's 1977 debut solo album "Pacific Ocean Blue". The song was released as a single in the United States, with the B-side being "Friday Night". The single failed to chart. The track, as with the rest of the album, was credited as being produced by Dennis Wilson and his close friend Gregg Jakobson.
Document 12: Breakaway (Kelly Clarkson song): "Breakaway" is a song recorded by American singer Kelly Clarkson. The song, written by Matthew Gerrard, Bridget Benenate and Avril Lavigne, was originally intended for Lavigne's debut studio album, "Let Go" (2002). After being deemed unsuitable for the album, it was passed to Clarkson to be recorded as a soundtrack for the film "". Clarkson, who was finishing her second studio album at that time, recorded "Breakaway" to tide her fans over until the first single from her new album was released. However, the song's success prompted its inclusion on Clarkson's second album where she decided to name the album after the song. "Breakaway" was first released by Walt Disney Records as the first single from on July 19, 2004. In May 2006, "Breakaway" was reissued as the fifth and final single from the album of the same name.
Document 13: Break Away (The Beach Boys song): "Break Away" is a song written by Brian and Murry Wilson for American rock band the Beach Boys, released as a single in 1969. Murry was credited as lyricist under the pseudonym "Reggie Dunbar". The single was relatively unsuccessful compared to the group's releases, and charted at No. 63 in the US "Billboard" 100 (top 40 in the "Cash Box" and "Record World" charts). "Break Away" sold better abroad, reaching No. 6 in the UK, No. 10 in Ireland, No. 17 in the Netherlands, No. 20 in New Zealand, and No. 29 in Germany.
Document 14: Farewell My Friend: "Farewell My Friend" is a song written by Dennis Wilson. It was released as the tenth track for his 1977 solo album "Pacific Ocean Blue". The song was released as a single in Europe as the B-side of the "River Song" single. The single however, failed to chart. The track, as with the rest of the album, was credited as having been produced by Dennis Wilson and his close friend Gregg Jakobson. Dennis Wilson sings the lead vocals on this and every other track on the album. The song also features vocals from his brother, Carl Wilson.
Document 15: Roy Orbison's Many Moods: Roy Orbison's Many Moods, also known as The Many Moods of Roy Orbison, is the thirteenth album recorded by Roy Orbison, and his seventh for MGM Records, released in May 1969. It included two singles, both of which were minor hits in the UK; "Heartache", which just missed the Top Forty, stalling at #44, and "Walk On", which scraped into the same chart, stopping at #39.
ground_truth: America
sub_queries: River Song >> performer Answer: Dennis Wilson
Dennis Wilson >> father Answer: Murry Wilson
Murry Wilson >> country of citizenship Answer: America