1. Brodlie, K.W., Butt, S.: Preserving convexity using piecewise cubic interpolation. Comput. Graph. 15, 15–23 (1991)
2. Brodlie, K.W., Mashwama, P., Butt, S.: Visualization of surface data to preserve positivity and other simple constraints. Comput. Graph. 19(4), 585–594 (1995)
3. Sarfraz, M., Hussain, M.Z., Hussain, M.: Shape-preserving curve interpolation. Int. J. Comput. Math. 89(1), 35–53 (2012)
4. Beliakov, G.: Monotonicity preserving approximation of multivariate scattered data. BIT 45(4), 653–677 (2005)
5. Goodman, T.N.T., Ong, B.H., Unsworth, K.: Constrained interpolation using rational cubic splines. In: Farin, G. (ed.) NURBS for Curve and Surface Design, SIAM, Philadelphia, pp. 59–74 (1991)