text: James Warnock, 56, has been convicted of the "horrifying" killing of Yiannoulla Yianni, 17, in 1982.
  She was attacked while home alone in Hampstead, north London, the Old Bailey heard.
  Warnock, formerly of Harrington Street, north-west London, was 22 at the time, and had denied the charges.
  The case was one of the Met Police's unsolved murders before DNA samples from the scene matched to the former tiler in December last year.
  In a victim impact statement Yiannoulla's family said: "For over half a lifetime we have had to live with the daily torture of what happened to our daughter and sister Lucy.
  "All who knew her, loved and adored her.
  "We now pray that we can move forward with the rest of our lives having some peace in knowing that her killer has been brought to justice and that a very dangerous man is no longer a threat to anyone else."
  It was not until 1999 that DNA could be extracted from the bedspread in the case.
  The court heard the Met Police got a "lucky break" in December when Warnock was arrested over indecent images of children and had to give a DNA sample.
  The sample was found to be a match to semen found at the murder scene.
  Reporting restrictions were lifted when Warnock admitted six indecent images offences relating to photos of young children and a baby in 2013 and 2015.
  Warnock had earlier described himself to the court as having been very slim with dark hair, styled like the actor John Travolta, at the time of the murder on 13 August 1982.
  Prosecutor Crispin Aylett QC told the trial that Yiannoulla had been with her parents parents Elli and George Yianni at their shoe repair shop a short distance from their home on the day of the attack, but went home early to prepare supper.
  A man in his early 20s was spotted chatting with to her on the doorstep, before a neighbour heard a scream about 20 minutes later, the jury heard.
  Her parents returned home to find jewellery scattered on the stairs and called out to her, before finding her partially naked body on their bed.
  During the trial he claimed he had been in a sexual relationship with the schoolgirl after meeting her at the family's shop, but the court heard she was a virgin before the attack.
  Warnock was living about half-a-mile from Yiannoulla's house at the time of her death, the court heard. Police said he had continued to live in the community in the years since the attack.
  After the killing, a public appeal, including a televised reconstruction featuring the victim's sister Maria, went out but despite more than 1,000 people coming forward with information, no real suspects were identified.
  Following the verdict, Det Insp Julie Willats said: "Lots of people came forward. Hundreds and hundreds of statements were taken over the years.
  "I got a lucky break. It's the science that has solved this one for us."
  "He must have known we would be coming for him.
  "I'm sure Warnock thought he'd never be caught but historic murders such as this are never 'case closed'."
target: A man who described himself in court as looking like John Travolta has been found guilty of the rape and murder of a teenager 34 years ago.