Crime author Patricia Cornwell has taken out full-page ads in two national newspapers to deny she is obsessed with Jack the Ripper.
The Ripper murdered prostitutes in London's East End
Cornwell claimed artist Walter Sickert was Jack the Ripper in a book in 2002. Ripper experts rejected that theory.
In Saturday's Guardian and Independent, Cornwell stands by her claim and calls on others to disprove it.
The ads are thought to have cost more than £10,000 each. An updated edition of her book will appear next year.
Cornwell wrote in the advert: "My ongoing investigation is far from an obsession but an excellent opportunity to provide a platform for applying modern science to a very old, highly visible case."
Cornwell has spent as much as $6m (£3.3m) financing her investigation into the Ripper case, including employing forensic scientists to work with her.
Her book Portrait of a Killer, Jack the Ripper: Case Closed named Sickert, a British Impressionist artist, as the infamous killer who terrorised London's East End in 1888.
Sickert, a pupil of Whistler, lived in London at the time. He died in 1942, aged 82.
The ads are said to have cost more than £10,000 each
Cornwell's main evidence was the discovery of the same watermarks on the artist's personal letters as on letters sent by Jack the Ripper, taunting the police.
But experts point out that many supposed "Ripper" letters were fakes and that Scotland Yard received such correspondence well into the 20th century.
They said Cornwell's evidence only showed a link between Sickert and these letters, not the murders themselves.
The author also put forward DNA evidence connecting Sickert to the crimes, but this was viewed as inconclusive.
While she has acknowledged she cannot prove Sickert was in London at the times of all the murders, she says it cannot be proved that he was elsewhere.
In Saturday's adverts, Cornwell called the case "far from closed" and challenged her critics to come up with concrete evidence of another suspect's guilt.
More than 115 years on, the mystery continues to intrigue
"I welcome everyone to investigate this case and perhaps find new evidence that factually argues for or against anything I have discovered," she wrote.
"If it turns out that something indisputably proved that this notorious killer was someone other than Walter Richard Sickert, I would be the first to offer congratulations and retract my accusations."
She adds that a revised edition of Portrait of a Killer, with her "latest" evidence, will be released early in 2006.