David Downing is the author of a political thriller, two alternative histories and a number of books on military and political history and other subjects as diverse as Neil Young and Russian Football.
A good introduction to Stalin and his social/economical reforms to the Soviet Union. While the book mentions his cruelty, paranoid reign of terror it doesn't go into specifics and presents the information in as unbiased a way as possible. For a better understanding students should not have this be their only resource.
I like topics about what happened during the wars. I already knew a little bit about Stalin but I learned a lot from this book. It tells his feelings while he did things, so we understand to know what type of person he is.