points = {{1, 4}, {.5, 6}, {5, 4}, {3, 12}, {11, 14}, {8, 4}, {12,
3}, {11, 9}, {15, 10}, {17, 8}};
knots = {0, 0, 0, 0, 1/8, 2/8, 3/8, 4/8, 5/8, 6/8, 7/8, 1, 1, 1, 1};
ParametricPlot[
deBoor[Append[points, First[points]], {3, knots}, t], {t, 0, 1},
Axes -> False]