Valentinov, N. 1879-1964. The early years of Lenin [electronic resource] / [by] Nikolai Valentinov (N. V. Volski). Translated and edited by Rolf H. W. Theen. Introd. by Bertram D. Wolfe.. — Ann Arbor, : University of Michigan Press, [c1969]. — xxii, 302 p. : ports. 22 cm.