Page 161 - Textos de Matemática Vol. 44

THE MAIN DIAGONAL PRODUCTS OF 3 × 3 NORMAL MATRICES 151 as we wished to show, concluding the proof of Theorem 1.1.
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(H. Nakazato) Department of Mathematical Sciences, Hirosaki University, 036-8561, Japan
E-mail address: nakahr@cc.hirosaki-u.ac.jp
(A. Kovaˇcec and N. Bebiano) CMUC, Department of Mathematics, University of Coimbra, Apartado 3008, EC Santa Cruz, 3001-501 Coimbra, Portugal
E-mail address: kovacec@mat.uc.pt; bebiano@mat.uc.pt
(J. da Providˆencia) Department of Physics, University of Coimbra, 3004-516 Coimbra, Portugal
E-mail address: providencia@teor.fis.uc.pt