Dejnoeka, Jan, cOrigins of Russell9s Early Theory of Logical Truth as Purely General Truth: Bolzano, Peirce, Frege, Venn, or MacColl?d, Modern Logic 8 (2000/2001), nos. 334, 21330
V. Peckhaus, Mathematical Reviews, M77063 (2002j:03002)  (2002).