Optimal p-interpolation error estimate is derived for the local, projection-based interpolation for H1-conforming elements in three space dimensions. Two different procedures leading to the same logarithmic term ln3/2 p in the estimate, are discussed. © 2005 Elsevier Ltd. All rights reserved.
Cao, W., & Demkowicz, L. (2005). Optimal error estimate of a projection based interpolation for the p-version approximation in three dimensions. Computers and Mathematics with Applications, 50(3–4), 359–366. https://doi.org/10.1016/j.camwa.2005.04.005