Question: Are both Kirk Windstein and Anthony Kiedis an American musician?

Context paragraphs:
Behind the Blackest Tears: Behind the Blackest Tears is the second studio album by Kingdom of Sorrow, a group featuring Jamey Jasta of Hatebreed and Kirk Windstein of Crowbar and Down.  The album was released by Relapse Records.

Anthony Kiedis: Anthony Kiedis ( ; born November 1, 1962) is an American musician who is the lead singer and songwriter of the band Red Hot Chili Peppers, which he has fronted since its inception in 1983.  Kiedis and his fellow band members were inducted into the Rock and Roll Hall of Fame in 2012.

Todd Strange: Todd Strange (born January 31, 1966) is a bassist who played live on the first Down album "NOLA" and with Crowbar.  Forming Crowbar with Kirk Windstein (Down), Matt Thomas and Craig Nunenmacher (Black Label Society), they released the best-selling albums of the band's discography.  This included the Crowbar self-titled LP with the hits "All I Had (I Gave)", "Existence is Punishment", "No Quarter" (by Led Zeppelin) and "I Have Failed", produced by Phil Anselmo.  By 1994, Phil put his band Pantera to the side and resurrected Down which was sidelined for Pantera in the late 1990s.  The band released NOLA in reference to the band's hometown, New Orleans, Louisiana, and played 13 shows.  Eventually, the album sold 500,000 copies and was certified Gold by the RIAA.  Soon after, Phil returned to Pantera and Crowbar continued, and the two bands partnered up for tours in 1996.  As a result, Todd, Kirk and the rest of Crowbar appear in Pantera's "Home Videos 3" in the credits, and Kirk and the band are seen in scenes including the notorious clip of Kirk dressed up as the Hulk.  This event is also included in Crowbar's 1996 home video "Like Broken", but contains slightly different footage.

Crowbar (album): Crowbar is the second studio album by New Orleans sludge metal band Crowbar, released on October 12, 1993.  The album sold 100,000 copies on the now defunct independent label Pavement Music.  The singles "All I Had (I Gave)" and "Existence Is Punishment" were played on MTV and received international attention.  "Crowbar" was produced by Phil Anselmo, a childhood friend of Crowbar's founder Kirk Windstein and the singer of Pantera, and recorded in New Orleans in 1992.

Kingdom of Sorrow: Kingdom of Sorrow is an American sludge metal band which features Kirk Windstein of Crowbar and Down, along with Jamey Jasta of Hatebreed.

Pepper Keenan: Pepper J. Keenan (born May 8, 1967), is an American guitarist and vocalist, best known for his work with heavy metal bands Corrosion of Conformity and Down.  He joined Corrosion of Conformity in 1989, but did not become the lead singer until the recording of "Deliverance" in 1994.  In 1991 he formed Down with Phil Anselmo of Pantera, Jimmy Bower of Eyehategod, and Kirk Windstein and Todd Strange of Crowbar.

Kirk Windstein: Kirk Windstein (born April 14, 1965) is an American musician.  He is a founding member of the sludge metal band Crowbar, and formerly played with the heavy metal band Down from 1991 to 2013.  In 2005, Windstein formed Kingdom of Sorrow with Jamey Jasta of Hatebreed.  Their debut album was released in 2008.  Windstein began his musical career in 1985 as a guitarist for a cover band called Victorian Blitz, and in 1988 joined a hardcore punk band called Shell Shock as a vocalist and guitarist.

Kingdom of Sorrow (album): Kingdom of Sorrow is the self-titled debut album by Kingdom of Sorrow, a group featuring Jamey Jasta of Hatebreed and Kirk Windstein of Crowbar and Down.  The album was released by Relapse Records.

Red Hot Chili Peppers 1983 Tour: The Red Hot Chili Peppers 1983 Tour was the first-ever concert tour by Red Hot Chili Peppers.  Originally formed as a joke band called "Tony Flow And The Miraculously Majestic Masters Of Mayhem" by bassist Flea, guitarist, Hillel Slovak and drummer, Jack Irons, all friends from high school.  They asked fellow high school friend, Anthony Kiedis to join them onstage for their first-ever show at the Hollywood, California venue known as The Rhythm Lounge.  Kiedis had previously been a MC to introduce his friend's former bands.  However, this time Kiedis was asked to sing.  With one song, a made-up rap Kiedis created called "Out In L.A.", the band took to the stage as an opening act for Neighbor's Voices.  The club owner was so impressed by their performance he told them to return the following week with another song.  The band quickly wrote "Get Up and Jump" and played it at that second show.  In early March 1983 the band made the name change to the Red Hot Chili Peppers.  The band first made a name for themselves on their local club scene when they played the famous Kit Kat Club by doing their now famous socks on cocks routine (this would become a trademark for the band and something they would do on occasion for many years).  After this performance, Lindy Goetz decided to be their manager, a role he would hold until 1999.  The 1983 tour consisted of shows mostly in the band's homestate of California except for one show in Nevada.  A 10-song demo tape was recorded with Spit Stix, drummer for the punk band Fear, which Flea was briefly with.

Down IV – Part I: Down IV – Part I (informally known as the The Purple EP) is the first EP by sludge/southern metal band Down.  It was released on September 18, 2012.  It is the first album featuring bassist Pat Bruders due to the departure of former bassist Rex Brown in 2011, and the last to feature guitarist Kirk Windstein, who left in 2013.

Supporting paragraphs: Kirk Windstein Anthony Kiedis
Answer: yes