311.2 Han S Hansen, Morris Howard, 1910- Sample survey methods and theory [by] Morris H. Hansen, William N. Hurwitz [and] William G. Madow. New York, J. Wiley [1966, c1953] 2 t. ilus. 24 cm. (Wiley publication in mathematical statistics) Contiene: t.1. ;ethods and applications.- t.2. Theory.