1. Clarifying some aspects of variance estimation in two-phase sampling;Beaumont;J. Surv. Stat. Methodol.,2015
2. A note on the concept of invariance in two-phase sampling designs;Beaumont;Surv. Methodol.,2016
3. A design-based perspective on missing data variance;Fay,1991
4. A generalization of sampling without replacement from a finite universe;Horvitz;J. Amer. Statist. Assoc.,1952
5. On sampling without replacement with varying probabilities;Narain;J. Indian Soc. Agricultural Statist.,1951