Here are some articles I found useful in writing about Bakunin & Berdyeav. I wrote a paper called
Slaver or Saviour?: Bakunin and Berdyaev on God and Freedom for my theology degree.

The Socialist Tradition from Moses to Lenin by Alexander Gray (London: Longmans, 1946). See Chapter 13.

A History of Russian Philosophy From the Tenth Through Twentieth Centuries Vol 1 and 2 Edited by Valery A Kuvakin (New York: Prometheus Books, 1994). Chapter 21 for Bakunin and chapter 45 for Berdyaev.

Religious and Anti-Religious Thought in Russia by George L. Kline (The Weil Lectures) (Chicago and London: The University of Chicago Press, 1968).

Philosophy in Russia: From Herzen to Lenin and Berdyaev by Frederick C. Copleston (University of Notre Dame Press, 1986). Especially chapter 14.

‘The Relation of God and Man in the Writings of Nicolas Berdyaev,’ by Donald G. M. Mackay, Scottish Journal of Theology Vol. 3, No. 4 (December 1950), 380-396.

‘The Philosophy of Freedom of Nikolai Berdiaev’ by Piama P. Gaidenko in Russian Thought after Communism: The Recovery of a Philosophical Heritage Edited by James P. Scanlan (Armonk; London: M.E. Sharp, 1994).