Brüdern, J, K. Kawada, and T. D. Wooley. “Additive Representation in Thin Sequences, V: Mixed Problems of Waring’s Type”. MATHEMATICA SCANDINAVICA 92, no. 2 (June 1, 2003): 181–209. Accessed May 5, 2024. https://www.mscand.dk/article/view/14400.