Mason Gaffney wrote: "However, Jan van Daal writes that Routledge has only published Etudes d'Economie Politique Applique thus far, and we may expect Etudes d'Economie Sociale very soon. I am grateful to have lived long enough to see this light at the end of the tunnel. It is remarkable, at least to me, that this latter work has been neglected, considering that its thesis parallels that of two very popular contemporary works in English: *Land Nationalization* by Alfred Russel Wallace, and *Progress and Poverty* by Henry George (whom Walras footnotes as "Henri-Georges")." It might be interesting to point out that a translated extract of Walras' *Etudes d'Economie Sociale*, entitled "The Theory of Property", is included in Peter Vallentyne & Hillel Steiner (Eds.), *The Origins of Left-Libertarianism. An Anthology of Historical Writings*, Palgrave, 2000, chapter 15, pp. 217-223. The previous chapter in that book is "The Injustice of Private Property" and comes from Henry George's *Progress and Poverty*. In the introduction, John Cunliffe traces the historical origins of left-libertarianism. Guido Erreygers