Brian Nielsen (boxer)
Brian Nielsen (born 1 April 1965) is a Danish former professional boxer who held the IBO heavyweight title.
Umar Salamov
Umar Salamov (born 7 June 1994, Alkhan-Kala, Russia) is a Russian light-heavyweight professional boxer.
 Salamov has held the WBO Youth World Light Heavyweight title, IBO Youth World Light Heavyweight title and the IBO World Light Heavyweight title.
 Salamov is currently ranked 8th in the WBO world rankings and 19th in Boxrec independent computerized rankings.
Calvin Brock
Calvin Vance Brock (born January 22, 1975 in Charlotte, North Carolina) is an American former professional boxer who competed from 2001 to 2007.
 In 2006, he won "Ring Magazine's" Knockout of the Year for his win against Zuri Lawrence and challenged for the IBF and IBO heavyweight titles.
 Brock was forced to retire after receiving retinal damage in his right eye following his loss to Eddie Chambers.
Neil Simpson (boxer)
Neil "Simmo" Simpson ( (1974--) 23 1974 (age (2017)-(1974)-((11)<(01)or(11)==(01)and(30)<(23)) ) ) born in London, now based in Coventry, is an English professional light heavy/cruiser/heavyweight boxer of the 1990s and 2000s, who won the British Boxing Board of Control (BBBofC) Midlands Area light heavyweight title, BBBofC British light heavyweight title, British Masters Cruiserweight title, and Commonwealth light heavyweight title, and was a challenger for the International Boxing Organization (IBO) Inter-Continental light heavyweight title against Darren Corbett, European Boxing Union (EBU) light heavyweight title against Yawe Davis, World Boxing Union (WBU) light heavyweight title against Tony Oakey, and BBBofC British light heavyweight title against Peter Oboh, his professional fighting weight varied from 169 lb , i.e. light heavyweight to 216 lb , i.e. heavyweight.
Steve Aczel
Steve Aczel ( (1954--) 08 1954 (age (2017)-(1954)-((11)<(09)or(11)==(09)and(30)<(08)) ) ) born in Budapest is an Australian professional light heavy/cruiser/heavyweight boxer of the 1980s, '90s and 2000s who won the Australasian light heavyweight title, Australian light heavyweight title, Australian heavyweight title, Oriental and Pacific Boxing Federation (OPBF) heavyweight title, Queensland State (Australia) heavyweight title, and Commonwealth light heavyweight title, drew with Maile Haumona for the South Pacific heavyweight title, and was a challenger for the Australian cruiserweight title against Tony Mundine, and Commonwealth cruiserweight title against Stewart Lithgo, his professional fighting weight varied from 172 lb , i.e. light heavyweight to 203+1/2 lb , i.e. heavyweight.
 He was inducted into the Australian National Boxing Hall of Fame in 2011.
Guy Waters
Guy "Arc Angel" Waters ( (1964--) 25 1964 (age (2017)-(1964)-((11)<(01)or(11)==(01)and(30)<(25)) ) ) is an Australian professional welter/light middle/middle/super middle/light heavy/cruiserweight boxer of the 1980s, 1990s and 2000s who won the New South Wales State (Australia) light heavyweight title, Australian light heavyweight title, Oriental and Pacific Boxing Federation (OPBF) light heavyweight title, Australasian Light Heavyweight Title, World Boxing Federation (WBF) light heavyweight title, International Boxing Federation (IBF) Pan Pacific super middleweight title, Oriental and Pacific Boxing Federation (OPBF) super middleweight title, and Commonwealth light heavyweight title, and was a challenger for the WBC light heavyweight title against Dennis Andries, World Boxing Association (WBA) World light heavyweight title against Virgil Hill, World Boxing Council (WBC) cruiserweight title against Juan Carlos Gómez, and Commonwealth super middleweight title against David Starie, his professional fighting weight varied from 167+1/2 lb , i.e. super middleweight to 185+1/4 lb , i.e. cruiserweight.
Erik Skoglund (boxer)
Erik Skoglund (born 24 May 1991) is a Swedish professional boxer.
 He currently holds the WBA International light heavyweight title.
 As of December 2016, he is ranked #12 in the world at light heavyweight.
 He previously held the IBO International light heavyweight title, the IBF Inter-Continental Light Heavyweight title, and the EBU-EU light heavyweight title which he defended three times.
Garry Delaney
Gary Delaney ( (1970--) 12 1970 (age (2017)-(1970)-((11)<(08)or(11)==(08)and(30)<(12)) ) ) born in Newham is an English professional light heavy/cruiser/heavyweight boxer of the 1990s and 2000s.
 He won the British Boxing Board of Control (BBBofC) Southern Area light heavyweight title, World Boxing Board (WBB) light heavyweight title, World Boxing Organization (WBO) Inter-Continental light heavyweight title, BBBofC Southern Area cruiserweight title, and Commonwealth light heavyweight title (twice), and was a challenger for the BBBofC British heavyweight title, and Commonwealth heavyweight title against Julius Francis, World Boxing Organization (WBO) Inter-Continental cruiserweight title against John Keeton, and Jesper Kristiansen, BBBofC British cruiserweight title, and Commonwealth (British Empire) cruiserweight title against Bruce Scott, and World Boxing Union cruiserweight title against Sebastiaan Rothmann, and Enzo Maccarinelli, his professional fighting weight varied from 174 lb , i.e. light heavyweight to 231 lb , i.e. heavyweight.
Crawford Ashley
Crawford "Chilling" Ashley (born Gary Crawford, 20 May 1964 in Leeds is an English professional super middle/light heavy/cruiser/heavyweight boxer of the 1980s, '90s and 2000s, who won the British Boxing Board of Control (BBBofC) Central Area light heavyweight title, BBBofC British light heavyweight title, European Boxing Union (EBU) light heavyweight title (twice), and Commonwealth light heavyweight title (twice), drew with Yawe Davis for the vacant European Boxing Union (EBU) light heavyweight title, and was a challenger for the European Boxing Union (EBU) light heavyweight title against Graciano Rocchigiani, World Boxing Association (WBA) World super middleweight title against Michael Nunn, World Boxing Association (WBA) World light heavyweight title against Virgil Hill, and World Boxing Union (WBU) cruiserweight title against Sebastiaan Rothmann, his professional fighting weight varied from 163 lb , i.e. super middleweight to 211 lb , i.e. heavyweight.

Question: What is the birthdate of this Danish former professional boxer who held the IBO heavyweight title and who worked with Mogens Palle?
Answer: 1 April 1965