PHADKE, B. B. Sublinearity and Convexity on the Grassmann Cone $G_2^4$. Mathematica Scandinavica, Berkeley, CA, United States, v. 30, p. 249–252, 1972. DOI: 10.7146/math.scand.a-11079. Disponível em: https://journals.msp.org/mscand/article/view/2249. Acesso em: 25 jul. 2026.