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Lua i Stíl Chicago (17ú heag.)Singh, Daroga. Theory and Analysis of Sample Survey Designs. New Delhi: Wiley, 1986.
Lua MLA (9ú heag.)Singh, Daroga. Theory and Analysis of Sample Survey Designs. Wiley, 1986.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.