Characterizing the sum of two cubes. Broughan, Kevin A. (2003) Journal of Integer Sequences [electronic only]
Corrigendum to "Representatons of multivariate polynomials by sums of univariate polynomials in linear forms" (Colloq. Math. 112 (2008), 201-233) A. Białynicki-Birula, A. Schinzel (2011) Colloquium Mathematicae