FERGUSON, Sarah H.; ROCHBERG, Richard. Higher order Hilbert-Schmidt Hankel forms and tensors of analytical kernels. Mathematica Scandinavica, Berkeley, CA, United States, v. 96, n. 1, p. 117–146, 2005. DOI: 10.7146/math.scand.a-14948. Disponível em: https://journals.msp.org/mscand/article/view/749. Acesso em: 24 jul. 2026.