@article{MET_1997__45_3_176704,
     author = {M. Luisa Targhetta},
     title = {A {Two-Stage} {Sampling} by {Unequal} {Size} {Samples} from {Two} {Normal} {Populations} with {Unknown} {Variances.}},
     journal = {Metrika},
     pages = {31--38},
     publisher = {mathdoc},
     volume = {45},
     number = {3},
     year = {1997},
     zbl = {0909.62015},
     url = {http://geodesic.mathdoc.fr/item/MET_1997__45_3_176704/}
}