Question: Walls Have Eyes was produced by a member of what band?

full_context: Document 1: The Walls Fell Down: "The Walls Fell Down" is a second single by the English rock duo The Marbles, Lead vocals by Graham Bonnet it was released in March 1969, and it was written and produced by Barry Gibb, Robin Gibb, Maurice Gibb, of the Bee Gees, and was also produced by Robert Stigwood, it was recorded as a follow-up to "Only One Woman" but did not repeat the success of the previous single.
Document 2: Maurice Gibb: Maurice Ernest Gibb, CBE ( ; 22 December 1949 – 12 January 2003) was a singer, songwriter, multi-instrumenatalist and record producer, who achieved fame as a member of the pop group the Bee Gees. Although his brothers Barry and Robin Gibb were the group's main lead singers, most of their albums included at least one or two compositions by Maurice, including "Lay It on Me", "Country Woman" and "On Time". The Bee Gees were one of the most successful rock-pop groups ever. Gibb's role in the group focused on melody and arrangements, providing backing vocal harmony and playing a variety of instruments.
Document 3: The Marbles (duo): The Marbles were an English rock duo that consisted of Graham Bonnet and Trevor Gordon, who operated between 1968 and 1969. Their only well-known singles were "Only One Woman" and "The Walls Fell Down". They also became associated with the Bee Gees members Barry, Robin and Maurice Gibb at that time.
Document 4: In Our Own Time: In Our Own Time is a biography of the musical group, The Bee Gees. The story follows the Brothers Gibb, Barry, Robin and Maurice from their roots in Manchester, England through their emigration to Australia in 1958 to their international stardom in 1967, right up to the present, with new interviews done by Barry and Robin and archival footage of Maurice (who died in 2003). Many live performances are featured, along with video clips, TV performances and home movies from their early days.
Document 5: Barry Gibb: Barry Alan Crompton Gibb, {'1': ", '2': ", '3': ", '4': "} (born 1 September 1946) is a singer, songwriter, musician, and record producer who rose to worldwide fame as a co-founder of the group Bee Gees, one of the most commercially successful and critically acclaimed groups in the history of popular music, with his brothers, Robin and Maurice Gibb. The three brothers also formed a songwriting partnership beginning in 1966.
Document 6: Robin's Reign: Robin's Reign was the first solo album by singer Robin Gibb, a member of the Bee Gees with his brothers Barry and Maurice. Robin had left the group following a disagreement with his brother Barry over who should sing lead vocals. The album was not a commercial success, though it did spawn Gibb's solo hit, "Saved by the Bell" (UK #2). The other songs in the album were produced by Gibb, and the rest was produced with his (then new) manager, Vic Lewis. This album was reissued by RSO Records in 1978 and reissued in 1991 on Spectrum Records. The album had a limited CD release in Germany and was made available digitally on Amazon and Spotify in 2011 and iTunes the following year. Gibb would not release another solo album until 1983.
Document 7: The Singer Sang His Song: "The Singer Sang His Song" is a song written by Barry, Robin and Maurice Gibb and recorded by the English rock group Bee Gees, released in early 1968 as a single along with Jumbo. In some countries the song was the B-side of Jumbo but in others they were promoted as a double A-side.
Document 8: Robin Gibb (EP): Robin Gibb is the first EP released by British singer-songwriter Robin Gibb, released in 1985 on Amiga Records only in Germany.
Document 9: Maurice Gibb: Maurice Ernest Gibb, CBE ( ; 22 December 1949 – 12 January 2003) was a singer, songwriter, multi-instrumenatalist and record producer, who achieved fame as a member of the pop group the Bee Gees. Although his brothers Barry and Robin Gibb were the group's main lead singers, most of their albums included at least one or two compositions by Maurice, including "Lay It on Me", "Country Woman" and "On Time". The Bee Gees were one of the most successful rock-pop groups ever. Gibb's role in the group focused on melody and arrangements, providing backing vocal harmony and playing a variety of instruments.
Document 10: Robin Gibb: Robin Hugh Gibb (22 December 1949 – 20 May 2012) was a singer, songwriter and record producer, who gained worldwide fame as a member of the pop group the Bee Gees, with his brothers Barry and Maurice Gibb, his fraternal twin. Robin Gibb also had his own successful solo career.
Document 11: Walls Have Eyes: Walls Have Eyes is the fourth solo album released by British singer-songwriter Robin Gibb. It was released in November 1985 on EMI America Records in the US and Polydor Records throughout the rest of the world, and produced by Maurice Gibb and Tom Dowd. The two singles from the album, "Like a Fool" and "Toys", did not chart in the US and UK. Gibb did not release a solo album in eighteen years until 2003 with "Magnet". Unlike "Secret Agent" which contains dance numbers, this album contains mostly ballads.
Document 12: Eye (album): Eye is the eighth studio album and fourth solo album by Robyn Hitchcock. It was released in 1990 on Glass Fish (UK) and Twin/Tone Records (US) and is his fourth solo album, and eighth studio album including his work with The Egyptians. This was Hitchcock's only solo album released between 1985 and 1995, a period in which he recorded most of his music with his backing band, the Egyptians.
Document 13: Robin Gibb: Robin Hugh Gibb (22 December 1949 – 20 May 2012) was a singer, songwriter and record producer, who gained worldwide fame as a member of the pop group the Bee Gees, with his brothers Barry and Maurice Gibb, his fraternal twin. Robin Gibb also had his own successful solo career.
Document 14: Walls and Bridges: Walls and Bridges is the fifth studio album by English musician John Lennon. It was issued by Apple Records on 26 September 1974 in the United States and on 4 October in the United Kingdom. Written, recorded and released during his 18-month separation from Yoko Ono, the album captured Lennon in the midst of his "Lost Weekend". "Walls and Bridges" was an American "Billboard" number-one album and featured two hit singles, "Whatever Gets You thru the Night" and "#9 Dream". The first of these was Lennon's first number-one hit in the United States as a solo artist, and his only chart-topping single in either the US or Britain during his lifetime.
Document 15: Bee Gees: were a pop music group formed in 1958. Their lineup consisted of brothers Barry, Robin, and Maurice Gibb. The trio were successful for most of their decades of recording music, but they had two distinct periods of exceptional success: as a popular music act in the late 1960s and early 1970s, and as prominent performers of the disco music era in the mid-to-late 1970s. The group sang recognisable three-part tight harmonies; Robin's clear vibrato lead vocals were a hallmark of their earlier hits, while Barry's R&B falsetto became their signature sound during the mid-to-late 1970s and 1980s. The Bee Gees wrote all of their own hits, as well as writing and producing several major hits for other artists.
ground_truth: the Bee Gees