Departamento de Física, Escuela Superior de Física yMatemáticas, Instituto Politécnico Nacional, U. P. Adolfo López Mateos, Zacatenco, C.P. 07738, Mexico City, Mexico
Departamento de Física, Escuela Superior de Física yMatemáticas, Instituto Politécnico Nacional, U. P. Adolfo López Mateos, Zacatenco, C.P. 07738, Mexico City, Mexico
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