The B-spline recurrence relations of Chakalov and of Popoviciu (Q1414076)

The authors collect several early results about the famous B-splines and their recurrence relations when the knots are arbitrarily distributed on the real line. Usually, one thinks mostly of Curry and Schoenberg in the context of univariate B-splines and their many properties (who have undoubtedly made the most important contributions at that time), but the authors discuss several interesting facts that can be traced back to much earlier times and the authors Chakalov and Popoviciu.