KATH, Ines; UNGERMANN, Oliver. Spectra of Sub-Dirac Operators on Certain Nilmanifolds. Mathematica Scandinavica, Berkeley, CA, United States, v. 117, n. 1, p. 64–104, 2015. DOI: 10.7146/math.scand.a-22237. Disponível em: https://journals.msp.org/mscand/article/view/384. Acesso em: 24 jul. 2026.