CUBIC SPLINE INTERPOLATION AT A BIINFINITE KNOT SEQUENCE
无限多个基点上的三次样条函数插值

Schoenberg once proposed a problem on the existence and uniqueness of bo-unded cubic splines interpolating at a biinfinite knot sequence. Carl de Boor gave a sufficientcondition so that he solved part of the problem. This article made an improvment on Boor'sresult by giving a sufficient and necessary condition. Thus we have completely solved the pro-blem that Schoenberg proposed.