Agradecimentos: During this research both authors where partially supported by CNPq, Brazil. The second author was als,o partially supported by the Universita' di Roma, Tor Vergata , via an agreement with the Universidade Estadual de Campinas

Abstract: In this paper we discuss some results on semi-parallel submanifolds of space forms, with particular emphasis to the case of surfaces. We prove that a semi-parallel surface of a space form is, under some additional conditions, either flat or parallel

CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQ

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