Question: Are Cho Kyuhyun and Layne Staley both singers?

Context articles: Cho Kyu-hyun discography
Mad Season (band)
Hangover Music Vol. VI
Alice in Chains
List of songs recorded by Alice in Chains
Layne Staley: Angry Chair
Layne Staley
Died (song)
Cho Kyuhyun
List of awards and nominations received by Cho Kyuhyun

Cho Kyuhyun (better known by his mononym Kyuhyun) is a South Korean singer.
 His discography consists of one studio album, three extended plays, seven singles, three promotional singles, and seventeen soundtrack songs.
 He debuted as a member of South Korean boy band Super Junior in 2006 and subsequently became a part of its subgroup Super Junior-K.R.Y. in 2006 and Super Junior-M in 2008 as well as S.M. Entertainment's group SM the Ballad in 2010.
Mad Season was an American rock supergroup formed in Seattle, Washington in 1994 by members of three popular Seattle-based bands: Alice in Chains, Pearl Jam and Screaming Trees.
 Mad Season released only one album, "Above", and is best known for the single "River of Deceit".
 The band went on a semi-permanent hiatus in 1996 due to the band members' conflicting schedules and vocalist Layne Staley's problems with substance abuse.
 Attempts were made in the late 1990s to revive the group without Staley; however, the band dissolved following the death of bassist John Baker Saunders in 1999.
 Staley died three years later of a drug overdose.
Hangover Music Vol.
 VI is the fifth studio album by heavy metal band Black Label Society, released April 20, 2004.
 This album is a much more mellow affair than any other Black Label Society album, and some fans have recognized it as a nod back to Zakk Wylde's solo effort, "Book of Shadows", from 1996.
 The album contains a piano version of Procol Harum's 1967 No. 1 "Whiter Shade of Pale" and a song entitled "Layne," which is written in memory of Layne Staley of Alice in Chains.
Alice in Chains is an American rock band formed in Seattle, Washington, in 1987 by guitarist/vocalist Jerry Cantrell and drummer Sean Kinney, who then recruited bassist Mike Starr and lead vocalist Layne Staley.
 Mike Starr was replaced in 1993 by Mike Inez.
Alice in Chains is an American rock band formed in Seattle, Washington, in 1987 by guitarist and songwriter Jerry Cantrell and original lead vocalist Layne Staley.
  The initial lineup was rounded out by drummer Sean Kinney and bassist Mike Starr, who was replaced in 1993 by Mike Inez.
  Although never officially disbanding, Alice in Chains was plagued by extended inactivity from 1996 onwards due to Staley's substance abuse, which resulted in his death in 2002.
  The band reunited in 2005 for a live benefit show and toured in 2006 with William DuVall taking over as lead vocalist full-time.
  They have thence resumed releasing music.
Layne Staley: Angry Chair is a biography by Adriana Rubio about Layne Staley, the lead vocalist of the rock band Alice in Chains, published in January 2003.
 As it is known, the book "Layne Staley: Angry Chair — A Look Inside the Heart and Soul of an Incredible Musician" written by Adriana Rubio (Argentinean journalist and a fan of Alice in Chains), features 50 pages of photos of Staley's art work, sketches, diary entries, and childhood pictures.
 It also contains an alleged last interview of Staley that Rubio claimed that she conducted less than three months before he died from an overdose of heroin and cocaine, in April 2002.
 Rubio did extensive interviews with Staley's mother, Nancy Layne McCallum, and his sister, Liz (née Elmer) Coats, to write the book.
 It is named after Alice in Chains' famous song, "Angry Chair".
Layne Thomas Staley (born Layne Rutherford Staley, August 22, 1967 – April 5, 2002) was an American singer-songwriter who served as the lead vocalist of the rock band Alice in Chains, which he founded with guitarist Jerry Cantrell in Seattle, Washington, in 1987.
 Alice in Chains rose to international fame as part of the grunge movement of the early 1990s, driven partly by Staley's distinct vocal style, as well as the harmonized vocals between him and Cantrell.
"Died" is a song by Alice in Chains and the final one recorded with vocalist Layne Staley before his death in 2002.
 The song was included on the compilation albums "Music Bank" (1999) and "The Essential Alice in Chains" (2006).
Cho Kyu-hyun (born February 3, 1988), better known mononymously as Kyuhyun, is a South Korean singer and musical theatre actor.
 He is best known as a member of South Korean boy group Super Junior, its sub-groups Super Junior-K.R.Y., Super Junior-M and a former member of the South Korean ballad group S.M. the Ballad.
 He is one of the first four Korean artists to appear on Chinese postage stamps.
List of awards and nominations received by Cho Kyuhyun