@article{GDZPPN00245128X,
title = {A Contribution to the Theory of Unique Estimators for Horvitz and Thompson's Classes of Linear Estimators},
journal = {Metrika},
volume = {16},
year = {1970},
pages = {40-47},
zbl = {0184.42304},
url = {http://dml.mathdoc.fr/item/GDZPPN00245128X}
}
Prabhu Ajgaonkar, S.G. A Contribution to the Theory of Unique Estimators for Horvitz and Thompson's Classes of Linear Estimators. Metrika, Tome 16 (1970) pp. 40-47. http://gdmltest.u-ga.fr/item/GDZPPN00245128X/