Sorceress of the Witch World by Andre Norton
A long series of fantasy novels set in a parallel universe where magic works and, at the beginning of the series, is exclusively performed by women. The series combines many traits of high fantasy and sword and sorcery. It begins with what is now called the Estcarp cycle. These describes the adventures of Simon Tregarth from Earth, his witch wife Jaelithe, and their three children Kyllan, Kemoc and Kaththea.