The River, The Rock and The Redeemed: A History of Missions Work in the Luapula Province of Zambia, 1898 - 2012 by Robert Muir and published by Ritchie Publications.
The title of this book takes you to a special spot in central Africa. The River is the great Luapula. The rock is big enough to give 20-30 people shade from the hot Zambian sun. At this spot over the past 12 years a large conference site has been established. The believers in Christ are the Redeemed, those whose forebears had never heard the gospel until it reached these parts just over a hundred years ago.