Kerstin Gier

Kerstin Gier is a German author born on October 8, 1966, in Bergisch Gladbach, Germany. She is best known for her Ruby Red trilogy, a young adult time travel series that achieved international success and won the American Library Association Best Books for Young Adults Award. Gier has written numerous novels for both young adults and adults, and continues to live and write in Germany.

Bergisch Gladbach, Germany Oct 8, 1966 Wikipedia
Young Adult Adult Fiction Time Travel