@article{MET_1997__45_3_176721,
     author = {M. Rueda Garcia and A. Arcos Cebri\^an},
     title = {Variance {Estimation} {Using} {Auxiliary} {Information:} {An} {Almost} {Unbiased} {Multivariate} {Ratio} {Estimator.}},
     journal = {Metrika},
     pages = {171--178},
     publisher = {mathdoc},
     volume = {45},
     number = {3},
     year = {1997},
     zbl = {0886.62014},
     url = {http://geodesic.mathdoc.fr/item/MET_1997__45_3_176721/}
}