APA način citiranja

Usha, M. (1993). Sampling schemes providing unbiased ratio and regression estimators. Dept of statistics, University of Kerala.

Čikaški stil citiranja

Usha, M.S. Sampling Schemes Providing Unbiased Ratio and Regression Estimators. Thiruvananthapuram: Dept of statistics, University of Kerala, 1993.

MLA način citiranja

Usha, M.S. Sampling Schemes Providing Unbiased Ratio and Regression Estimators. Dept of statistics, University of Kerala, 1993.