What is the author's style in The People of Sparks by Jeanne DuPrau?

The author employs a shifting point of view throughout the story, sometimes presenting the same events from the points of view of different characters. Much of the story is told from the perspective of the two main characters Doon and Lina; however, some portions are told from the point of view of Torren, a secondary character. The author also includes chapters that are told from a narrative perspective and do not reflect any one character's point of view.