MDFEM: Multivariate decomposition finite element method for elliptic PDEs with lognormal diffusion coefficients using higher-order QMC and FEMDong T. P. Nguyen and Dirk NuyensESAIM: M2AN, 55 4 (2021) 1461-1505DOI: https://doi.org/10.1051/m2an/2021029