Authors: Espejo, M. R. Penas, J. S.

Citation: M. R. Espejo et J. S. Penas, Sampling design providing unbiased new product estimators,, Statistica, 50(2), 1990, pp. 285-288

Authors: Espejo, M. R. Santos_Penas, J.

Citation: M. R. Espejo et J. Santos_Penas, Unbiased mean-of-the-ratios estimators,, Statistica, 49(4), 1989, pp. 617-622