What has the author John Larsson written?

It seems you might be thinking of John Ajvide Lindqvist, the Swedish author who wrote the following books:

* Let the Right One In (2004) - a horror novel about a young boy who befriends a vampire girl. It was adapted into a successful Swedish film and then an American remake.

* The Child (2006) - a psychological horror novel about a woman who discovers a strange and sinister entity in her apartment.

* The Woman in the Spiders' Web (2008) - a continuation of the Lisbeth Salander series created by Stieg Larsson.

* The Girl Who Played with Fire (2009) - a sequel to *The Girl with the Dragon Tattoo* by Stieg Larsson, also written by Lindqvist.

There is no known author named "John Larsson". If you meant someone else, please provide more information about the author or their work.