1953a. [Translator and editor]. Louis Hjelmslev: Prologomena to a Theory of Language [Omkring sprogteoriens grundlæggelse] [= International Journal of American Linguistics, memoir 7] (trans. and ed.: FJW). Bloomington: Indiana University Press. Collaborator with Louis Hjelmslev on revised edition, Madison-Milwaukee-London: University of Wisconsin Press, 1961. Reprinted 1963, 1969.
· Foreign-language editions based on the first English edition:
o Russian: Prolegomeny k teorii jazyka. Lekomcev (trans.: Ju.K.). Novoe v lingvistike 1 (ed. and introd.: V.A. Zveginceva). Moscow, 1960, 264-389.
o Romanian: Preliminarii la o teorie a limbii (trans.: D. Copceag). Bucharest: Centrul de cercetǎri fonetice şi dialectale, 1967.
o French: Prolégomènes à une théorie du langage (trans.: Anne-Marie Léonard et al.). Les Éditions de Minuit, 1968.
o Czech: O základech teorie jazyka (trans.: František Čermák). Prague: Academia, 1972.
o German: Prologomena zu einer Sprachtheorie (trans.: Rudi Keller, Ursula Scharf, and Georg Stötzel). Münich: Hüber, 1974.
o Portuguese: Prologômenos a uma Teoria da Linguagem. Sao-Paulo: Perspectiva, 1975.
· Foreign-language editions based on the revised English edition:
o Italian: I fondamenti della teoria del linguaggio (trans. and introd.: C. Giulio Lepschy). Torino: Giulio Einaudi, 1968.
o French: Prolégomènes á une théorie du langage (trans.: Una Canger). (Arguments, 35.) Paris: Les Éditions de Minuit, 1971.
o Spanish: Prolegómenos a una teoría del lenguaje (trans.: José Luis Díaz Liaño). (Biblioteca Románica Hispánica, Estudios y ensayos, 155.) Madrid: Editorial Gredos, 1971. 2nd ed. 1974
1970b. [Translator and editor]. Louis Hjelmslev: Language: An Introduction [Sproget. En introduktion] (ed.: FJW). Introduction by FJW and a concluding chapter, Languages of Different Degrees, taken from Hjelmslev’s posthumous papers. Madison-Milwaukee-London: University of Wisconsin Press, 1970.
· Foreign-language editions based on the English edition:
o Czech: Jazyk (trans.: Miloš Dokulil). Prague: Academia, 1971.
o Spanish: El lenguaje (trans.: María Victoria Catalina). Madrid: Editorial Gredos, 1971.
o Danish: Sproget. En introduktion (eds.: P.H. Jensen and FJW). Copenhagen: Museum Tusculanums Forlag, 1984.