In God's Underground, by Richard Wurmbrand, is a 355 page book telling the stories of how Richard Wurmbrand ministered in prison to other prisoners.
100 Prison Meditations
With God In Solitary Confinement
Share Their Voice: Sarah's Story
The Witnesses Trilogy: God With Us
The Torchlighters: The John Bunyan Story
The Torchlighters: The Corrie Ten Boom Story