Trích dẫn APA

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

Trích dẫn kiểu Chicago

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

Trích dẫn MLA

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

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