@article{MET_1991__38_2_176324,
     author = {P.C. Gupta and V.D. Naik},
     title = {A {General} {Class} of {Estimators} for {Estimating} {Population} {Mean} {Using} {Auxiliary} {Information.}},
     journal = {Metrika},
     pages = {11--17},
     publisher = {mathdoc},
     volume = {38},
     number = {2},
     year = {1991},
     zbl = {0714.62008},
     url = {http://geodesic.mathdoc.fr/item/MET_1991__38_2_176324/}
}