( CNN ) The smallest of clues can help to crack a case . That 's what authorities in Oklahoma are hoping in the 34-year-old murder of Tracey Neilson . They 've released images of an old cable repair ticket book , and are asking for the public 's help in identifying the owner of that book . The last ticket in the book is for work done at Neilson 's home the morning she was murdered -- January 5 , 1981 . She was celebrating her 21st birthday that day . `` At 5 o'clock that evening , Jeff Neilson , Tracey 's husband of only five months , found her dead inside their apartment at the Jamestown Square Apartments in Moore , '' the Oklahoma State Bureau of Investigation said in a statement . `` Tracey had been stabbed numerous times . Moore police responded to the scene and began investigating . The next day , the Moore Police Department requested OSBI assistance with the case . During the next 34 years , dozens of OSBI agents would work on the case . '' They followed more than 1,500 leads , the statement said . On a bottom corner of the book is a box for an employee name . Authorities want to identify the three letters written in that box . They are offering up to $ 11,000 for information leading to the arrest and conviction of the person who killed Neilson .
Tracey Neilson was stabbed to death January 5 , 1981 . Police say they have investigated over 100 leads . Police released a picture of a cable repair ticket book to help identify initials in the murders .