Question: What is the birthdate of this English former footballer who played as a striker and who played for the 2012-13 Sheffield United F.C. season?

full_context: Document 1: List of Premier League hat-tricks: Since the inception of the English football league competition, the Premier League, in 1992, more than 100 players have scored three goals (a hat-trick) or more in a single match. The first player to achieve the feat was Frenchman Eric Cantona, who scored three times for Leeds United in a 5–0 victory over Tottenham Hotspur. Twenty players have scored more than three goals in a match; of these, five players, Andy Cole, Alan Shearer, Jermain Defoe, Dimitar Berbatov and Sergio Agüero have scored five. Sadio Mané holds the record for the quickest Premier League hat-trick, netting three times for Southampton against Aston Villa in 2 minutes 56 seconds, breaking Robbie Fowler's record, while in 1999, Manchester United player Ole Gunnar Solskjær scored four goals in twelve minutes as a substitute against Nottingham Forest, "the fastest scorer of a four-goal haul on record in England".
Document 2: Bobby Davison: Robert "Bobby" Davison (born 17 July 1959) is an English former professional footballer who played as a striker. Born in South Shields he began his career with Huddersfield Town before spending time at Halifax Town, Derby County (twice), Leeds United, Sheffield United (twice), Leicester City, Rotherham United and Hull City. After he retired from playing he spent time on the coaching staff of a number of clubs, including brief spells as manager of Guiseley and Ferencváros, and is currently youth team coach at Crystal Palace and assistant manager to Noel Blake's England national under-19 football team.
Document 3: Dave Kitson: David Barry Kitson (born 21 January 1980) is an English former footballer who played as a striker. He has made 420 appearances in the Premier League and Football League, including 135 for Reading.
Document 4: 1995–96 Sheffield United F.C. season: The 1995-96 season was the 107th season in existence for Sheffield United, during which they played in Division One for the second successive season. In the first half of the season events in the boardroom overshadowed those on the pitch until Mike McDonald completed a successful take over of the club. Following his arrival manager Dave Bassett resigned and was replaced by Howard Kendall who was provided with the funds to overhaul the squad. A large number of changes were made to the playing squad over the following months meaning the club used more first-team players in one season than ever before. Although struggling for much of the season the new arrivals brought about a late rally and the club finished a respectable ninth in the division.
Document 5: 1992–93 Sheffield United F.C. season: During the 1992–93 English football season, Sheffield United competed in the inaugural season of the FA Premier League under manager Dave Bassett.
Document 6: 2013–14 Sheffield Wednesday F.C. season: During the 2013–14 football season, Sheffield Wednesday Football Club will compete in three professional football competitions. Sheffield Wednesday will compete in the 2013–14 Football League Championship, 2013–14 FA Cup, and the 2013–14 Football League Cup. It will be the Owls' second consecutive season in the Football League Championship having secured promotion from League One in the 2011–12 season and then securing Championship safety on the last day of the 2012–13 season. The Football League season will kick-off at the beginning of August, along with the League Cup in the same month. Meanwhile, with Sheffield Wednesday being within the top two-tiers of the English football league system the club doesn't enter the FA Cup until the beginning of January 2014 where they enter at Round 3 of the competition.
Document 7: 2012–13 Oxford United F.C. season: Oxford United F.C. season 2012–13 was the club's third season in League Two after returning from the Conference. Oxford United had finished 9th in League Two in 2011–12 and failed to improve on this position in 2012–13. The club's opening nine league fixtures, consisting of three wins followed by six defeats, set the tone of a campaign in which the club were never serious contenders for a playoff place and which alternated between winning and losing streaks; a case in point was the three-game run of victories at the end of the season after the possibility of promotion had disappeared, which put a somewhat flattering gloss on Oxford's final position. They were knocked out by higher-division opposition in the early rounds of both the FA Cup and League Cup (including elimination at the hands of Sheffield United from the former competition for the second year in succession), but reached the Area Semi-final of the Football League Trophy and won the Oxfordshire Senior Cup.
Document 8: David Platt (footballer): David Andrew Platt (born 10 June 1966) is an English former professional footballer who played as a midfielder.
Document 9: Les Ferdinand: Leslie "Les" Ferdinand MBE (born 8 December 1966) is an English former footballer and current football coach and Director of Football at his former club Queens Park Rangers. A former striker, his playing career included spells at Queens Park Rangers, Beşiktaş, Newcastle United, Tottenham Hotspur, West Ham United, Leicester City, Bolton Wanderers, Reading and Watford during which period he earned 17 caps for England. Ferdinand is the eighth highest scorer in the Premier League with 149 goals.
Document 10: 1993–94 Sheffield United F.C. season: The 1993-94 season was the 105th season in existence for Sheffield United, during which they played in the Premier League under manager Dave Bassett. With little money to spend to improve the side it was a season of struggle which ended in relegation.
Document 11: Gareth Barry: Gareth Barry (born 23 February 1981) is an English professional footballer who plays as a midfielder for West Bromwich Albion. He is the player with the highest number of appearances in the Premier League.
Document 12: 2012–13 Sheffield United F.C. season: Sheffield United Football Club participated in League One, the third level of English football in 2012–13, after having failed to win promotion, losing in the previous season's play-off final. Danny Wilson remained in charge for a second season and the club continued to reduce costs as they sought to adapt to life at the third level of English football. Many of the players involved in the previous season were either sold or released, while the likes of Nick Blackman, Tony McMahon, Shaun Miller and Dave Kitson were signed to replace them.
Document 13: David Kitson (cricketer): David Lees Kitson (13 September 1925 – 6 May 2002) was an English cricketer. He was a right-handed batsman who played 32 games scoring 882 runs for Somerset between 1952 and 1954. He was born in Batley, Yorkshire and died in Ilminster, Somerset.
Document 14: 2012–13 Rochdale A.F.C. season: The 2012–13 season is the 92nd season of competitive football for Rochdale A.F.C., a professional English football club based in Rochdale, Greater Manchester. Rochdale return to Football League Two for 2012-13 following a two-season stint in League One which ended with a last-place finish in 2011-12. Rochdale began their 2012–13 Football League Two season with a 0-0 draw with Northampton. They entered into three cup competitions in the first round due to the league table they are in. John Coleman's and Jimmy Bell's contracts were terminated by Rochdale on 21 January 2013 following a poor run in form.
Document 15: 2011–12 Rotherham United F.C. season: Following Rotherham's defeat to Oxford United on 17 March 2012, the club found themselves eight points from the play-off places in League Two. This prompted chairman Tony Stewart to sack Andy Scott two days later. Steve Evans was appointed as the new manager on a 3-year deal on 9 April.
ground_truth: 21 January 1980