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2. Complex Analytic Methods for Partial Differential Equations. An Introductory Text (World Sci., Singapore, 1994).
3. Second order Cauchy-Pompeiu representations, in: Complex Methods for Partial Differential Equations, edited by H. Begehr, A. O. Celebi, and W. Tutschke (Kluwer, Dordrecht, 1999), pp. 165-188.
4. Integral representations for differentiable functions, in: Problemi Attuali dell'Analisi e della Fìsica Matemàtica, edited by P. E. Ricci (Aracne, Roma, 2000), pp. 111-130.