Victorious Faith, by Richard Wurmbrand, is a 128 page book that shares the Christian faith that sustained him while he was in prison.
Between Two Tigers
The Torchlighters: The Jim Elliot Story
The Torchlighters: The Adoniram and Ann Judson Story
Christian Witness Among Muslims
The Witnesses Trilogy: To Every Nation
The Torchlighters: The Harriet Tubman Story