1. Optimal designs for sampling in two dimensions;Bellhouse;Biometrika,1977
2. Sampling with unequal probabilities;Berger,2009
3. Sampling Techniques;Cochran,1977
4. Variance estimation in the swedish consumer price index;Dalén;J. Bus. Econom. Statist.,1995
5. Multilevel Statistical Models;Goldstein,2011