Perepiska G.V. Plekhanova i P.B. Akselʹroda /
Plekhanov, Georgiĭ Valentinovich,1856-1918.
Berlin, P. A.
Voĭtinskiĭ, V. S.
Nikolaevsky, Boris I.
The Hague,
1967.
Facsimile reprint of the 1925 edition, Moscow.