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2. D. N. Clark and J. H. Morrel, ?On Toeplitz operators and similarity,? Am. J. Math. (to appear).
3. D. N. Clark, ?Sz.-Nagy-Foia? theory and similarity for a class of Toeplitz operators,? Proc. 1977 Spectral Theory Semester, Stefan Banach Inst., Warsaw (1977).
4. B. Sz.-Nagy and C. Foia?, ?On the structure of intertwining operators,? Acta. Sci. Math.,35, 225?254 (1973).
5. D. N. Clark, ?Similarity properties of rational Toeplitz operators? (in preparation).