A useful sketch of recent biographies is to be found in The Edinburgh Review (July 1906).
He also wrote biographies of Frederick the Great and Frederick William IV.
Biographies are prefixed to most of the above editions.
Many of the most celebrated men of Europe visited him there, and large parts of his usual biographies are composed of extracts from their accounts of Ferney.
Baker, the writings of Livingstone, and the biographies of Gordon may be consulted, besides the many documents on these subjects published by the British and Foreign Anti-Slavery Society.