Question: Are Bruce Dickinson and Robin Zander both leader singers of a band?

Context articles: The Book of Souls World Tour
Cheap Trick
Robin Zander (album)
I've Always Got You
The Wicker Man (song)
List of songs recorded by Iron Maiden
Bruce Dickinson
Robin Zander
Born in '58
Next Position Please

The Book of Souls World Tour was a concert tour by Iron Maiden, held in support of their sixteenth studio album, "The Book of Souls".
 The first leg of the tour saw the band play shows in 36 countries across six continents, which included their debut performances in El Salvador, Lithuania and China.
 With 117 shows, it was the longest tour with Bruce Dickinson on vocals since the "Somewhere on Tour" in 1986-87.
 The group, their crew and equipment were transported on a customised Boeing 747-400, nicknamed "Ed Force One", which was piloted by vocalist Bruce Dickinson.
Cheap Trick is an American rock band from Rockford, Illinois, formed in 1973.
 The band currently consists of vocalist Robin Zander, guitarist Rick Nielsen, bassist Tom Petersson and touring drummer Daxx Nielsen.
 Original drummer Bun E. Carlos stopped touring with the band in 2010 but remains a partner in their business organization.
Robin Zander is the debut solo album from American singer Robin Zander of Cheap Trick.
 It was released in 1993 by Interscope Records.
"I've Always Got You" is a single by American vocalist Robin Zander, best known as lead vocalist for the American rock band Cheap Trick.
 The single was released in 1993 as the lead single from Zander's debut solo album "Robin Zander".
 The song was written by Mike Campbell of Tom Petty and the Heartbreakers fame, Zander and J.D. Souther.
"The Wicker Man" is a song by Iron Maiden, released as the first single and opening track from their album "Brave New World" in April 2000.
 It is also the first single by the band since the returns of vocalist Bruce Dickinson and guitarist Adrian Smith in 1999.
 It was co-written by Smith, Dickinson and Steve Harris.
 It was co-produced by Kevin Shirley and Harris.
 The title is inspired by the British cult film of the same name.
 The song should not be confused with "Wicker Man" from Dickinson's solo career, the lyrics of which are more closely themed around the film.
 The latter song can be found on the 2 disc edition of "The Best of Bruce Dickinson".
Iron Maiden are an English heavy metal band formed by bassist Steve Harris in 1975.
 The band's first album, 1980's "Iron Maiden", was written primarily by Harris, with vocalist Paul Di'Anno co-writing two tracks and guitarist Dave Murray contributing "Charlotte the Harlot".
 The 1981 follow-up, "Killers", was written almost entirely by the bassist, with frontman Di'Anno contributing only to the title track, "Killers" (the North American bonus track "Twilight Zone" was credited to Harris and Murray).
 Bruce Dickinson replaced Di'Anno after the release of "Killers", although he did not contribute any songwriting to "The Number of the Beast", released in 1982, which featured three songs co-written by guitarist Adrian Smith.
 "The Number of the Beast" also spawned Iron Maiden's first UK Singles Chart top ten in the form of "Run to the Hills", which charted at number seven on its release.
 It was not until 1983's "Piece of Mind" that the songwriting process became a more varied and collaborative approach, with just four of its nine tracks being credited solely to Harris, two to Dickinson and Smith, one to Harris and Murray, one to Dickinson alone, and one to Harris, Dickinson, and Smith.
 The Dickinson and Smith-penned "Flight of Icarus" was the first Iron Maiden single to chart in the United States, reaching number eight on the "Billboard" Mainstream Rock chart.
Paul Bruce Dickinson (born 7 August 1958), known professionally as Bruce Dickinson, is an English singer, songwriter, musician, airline pilot, entrepreneur, author and broadcaster.
 He is the lead singer of the heavy metal band Iron Maiden and is renowned for his wide-ranging operatic vocal style and energetic stage presence.
Robin Zander (born January 23, 1953) is the lead singer and rhythm guitarist for the rock band Cheap Trick.
"Born in '58" is the last single from Bruce Dickinson's debut solo album, "Tattooed Millionaire", released on March 25 1991.
 The song is about Bruce Dickinson's early life, growing up with his Grandparents in Worksop (Dickinson was born in 1958).
Next Position Please is the seventh studio album by American rock band Cheap Trick, produced by Todd Rundgren and released in 1983.
 The title track was originally demoed for the band's 1979 album "Dream Police", which had lead singer Robin Zander, lead guitarist Rick Nielsen, and bassist Tom Petersson each singing a verse.
 The song did not go beyond a demo, but it was referenced in "High Priest of Rhythmic Noise", a track from 1980's "All Shook Up".
 "Position" was eventually re-recorded for this album, and features only Zander singing.