If you don't have a pdf file of it and you have a .tax or .tax20yy file you need that year's program to open it. You can buy the past 3 years programs from Turbo Tax or find them on Ebay, etc.
OR you could try the TaxPrinter service at
http://www.taxprinter.com They might be expensive and it is probably not safe to email tax returns back and forth Their Website says…….
We read most federal and state files (Windows and Macintosh) from years 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013... Known exceptions are TurboTax 1997 and TaxCut 2005 files which we can't read for technical reasons.
OR get a copy from the IRS -
http://www.irs.gov/Individuals/Get-Transcript