* Roger William Pethybridge (1990), "One Step Backwards, Two Steps Forward: Soviet Society and Politics in the New Economic Policy", Oxford University Press, ISBN 978-0-19-821927-9.
* Roger William Pethybridge (1990), "One Step Backwards, Two Steps Forward: Soviet Society and Politics in the New Economic Policy", Oxford University Press, ISBN 978-0-19-821927-9.