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I am hoping someone may know this book based upon the plot:
An advanced race visits a planet that is technologically equivalent to the dark ages. To interact with the inhabitants these visitors allow them to think they are magical. In particular the daughter of one of the visitors has to pretend to be a magical sorceress.
The planet is then also visited by an Earth ship that is not as advanced as the first set of visitors. Their goal is to deal with the inhabitants for natural resources. The advanced visitors try to prevent the Earth people from exploiting the planet while remaining unknown to the Earth people.
The story switches between 3 different points of views:
- The daughter of the advanced visitors as she pretends to be the magical sorceress
- A peasant boy who interacts with the "sorceress" and becomes somewhat infatuated with her
- An earthman who is trying to obtain the deal for the natural resources of the planet.