TUCSON, Ariz. — The Pima County Sheriff's Department released a pair of ransom notes Friday in the hope that someone can identify the author.Authorities have not yet confirmed that the notes are authentic, but Guthrie's daughter, "Today" co-host Savannah Guthrie, has said she believes they may be — and investigators haven't ruled them out either.GOT A TIP?They were sent on Feb. 2 and Feb. 6.NEW DETAILS FROM NANCY GUTHRIE RANSOM DEMAND REVEALED, 'HER LIFE IS IN YOUR HANDS': REPORTAccording to the sheriff's department, the two notes share a "unique linguistic style" and are believed to have been sent by the same person.FOLLOW THE FOX TRUE CRIME TEAM ON XSIGN UP TO GET THE LATEST TRUE CRIME NEWSLISTEN TO THE NEW 'CRIME & JUSTICE WITH DONNA ROTUNNO' PODCASTThe style is so distinct, that someone may be able to recognize the writer, authorities said.Anyone with information is asked to dial 1-800-CALL-FBI or, to remain anonymous, call 520-88-CRIME.SAVANNAH GUTHRIE'S EMOTIONAL PLEA TO MOM'S KIDNAPPER MAY SIGNAL 'NEW LINE OF COMMUNICATION': REPORTThis is a breaking news story.