ECS Ministries has discipleship books they sell on their online store. There are English discipleship books and there are books printed in other languages.
International Prison Ministry (IPM)
IPM provides many biblical resources for prisoners, for the purposes of evangelism and edification. The books featured on their website are testimonies of former prisoners who had their lives transformed through relationship with Jesus Christ. From sinners being saved by grace through faith in Jesus Christ, to growing into godly, fruitful people as His disciples now ministering to others, these are a selection of their stories.
If you have any questions or need help finding a particular video, tract, book or any other Christian resource in any language of the world, please contact firstname.lastname@example.org