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Studies on Predication in Russian I, Santa Monica, CA, 1964.
Studies on Predication in Russian II, Santa Monica, CA, 1965.
Problems of Typological and Genetic Linguistics Viewed in a Generative Framework, The Hague, 1970.
On Medieval and Renaissance Slavic Writing. Selected Essays, The Hague, 1974.
Common Slavic: Progress and Problems in its Reconstruction, Cambridge, MA, 1975, 21979.
Doktor Faustus und Doktor Schiwago. Versuch ueber zwei Zeitromane aus Exilsicht, Lisse, 1976.
Linguistic Reconstruction: Its Potentials and Limitations in a New Perspective, Washington, D.C., 1977.
Lord Novgorod the Great: Essays in the History and Culture of a Medieval City-State. Part One: The Historical Background, Columbus, OH, 1981.
Essays in Early Slavic Civilization / Studien zur Fruehkultur der Slaven, Munich, 1981.
Recent Advances in the Reconstruction of Common Slavic (1971-1982) [jointly with P.T. Merrill], Columbus, OH, 1984.
Lord Novgorod the Great: Sociopolitical Experiment and Cultural Achievement, Los Angeles, 1985.
Praslavianskii iazyk. Dostizhenia i problemy v ego rekonstruktsii, Moscow, 1987.
Novgorod and Dubrovnik: Two Slavic City Republics and Their Civlization, Zagreb, 1989.
Aspects of the Slavic Middle Ages and Slavic Renaissance Culture, New York, 1992.
Novgorod in Focus, Columbus, OH, 1996.