O. Davydov, Locally linearly independent basis for $C^1$ bivariate splines of degree $q\ge 5$, in "Mathematical Methods for Curves and Surfaces II" (M.Daehlen, T.Lyche, L.L.Schumaker, Eds.), pp. 71-78, Vanderbilt University Press, 1998.

Abstract: We construct a locally linearly independent basis for the space $\S^1_q(\Delta)q$ ($q\ge5$). Bases with this property were available only for some subspaces of smooth bivariate splines.

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