Together with Swedish-born Baron Axel de Reuterskiöld he wrote Les Timbres Postes de la Suisse 1843-1860 which was published in 1899.
The book is considered well-researched and the first published deep study of Swiss philately.
The book is still considered a standard reference and has been the basis for many more modern or more particular enquiries into the field of the Swiss classical issues.