中国科学院数学与系统科学研究院期刊网
TRIVARIATE POLYNOMIAL SPLINE INTERPOLATION WITH NATURAL BOUNDARY CONDITION FOR SCATTERED DATA
Xu Yingxiang, Yu Gaohang, Guan Lutai
Mathematica Numerica Sinica . 2011, (4): 423 -446 .  DOI: 10.12286/jssx.2011.4.423