Hansen, B. L. (1960). Work sampling for modern management. Prentice-Hall.
Lua i Stíl Chicago (17ú heag.)Hansen, Bertrand L. Work Sampling for Modern Management. Englewood Cliffs, N. J.: Prentice-Hall, 1960.
Lua MLA (8ú heag.)Hansen, Bertrand L. Work Sampling for Modern Management. Prentice-Hall, 1960.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.