MUTHURAMALINGAM, Pl. Spectral properties of vaguely elliptic pseudo differential operators with momentum dependent long range potentials using time dependent scattering theory - II. Mathematica Scandinavica, Berkeley, CA, United States, v. 58, p. 255–274, 1986. DOI: 10.7146/math.scand.a-12145. Disponível em: https://journals.msp.org/mscand/article/view/1485. Acesso em: 25 jul. 2026.