I have also read Coryne Hall's Little Mother and agree with everyone that it is a wonderful book and has certainly been incredibly well researched and I would highly recommened it. However, I also enjoyed the earlier biographies by Tisdall and Poliakoff.
I am a bit gutted not to be in a position to read the Russian Language biographies that are out there, especially as Svetabel recommends them. I believe there is also one in Danish as well.
Does anyone know if they are published online as I think my husband has found an AP for translating long texts. Don't ask me how that works, I've only just mastered making posts on this forum but if anyone could post a link I will let him look at it with his array of gadgets and IT skills.