8: John Green's the fault in our stars.
7: Mette Finderup's book series: The green island (a danish book series).
6: Stephine Perkins' book series: Anna and the french kiss, Lola and the boy next door and Isla and the happily ever after.
5: Suzanne Collins' book series: The Hunger Games.
4: Jay Asher's 13 reasons why.
3: J.R.R. Tolkien's book series: The hobbit.
2: J.R.R. Tolkien's book series: Lord of the rings.
1: J.K. Rowlings' book series: Harry Potter and Fantasic beasts and where to find them.