Barnes, Ralph M. (Ralph Mosser)
Work sampling
John Wiley & Sons, 1961
 Buku Teks SO
Allen, Robert E.
Contemporary labor relations / Robert E. Allen and Timoty J. Keaveny
Mass Addison-Wesley , 1983
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Hogins, J. Burl
Language introductory reader / J. Burl Hogins; Robert E. Yarber
Harper & Row, 1969
 Buku Teks SO
Richardon, William J.
Heidegger: through phenomenology to thought / William J. Richardson
Fordham University Press, 2003
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Hansen, Bertrand L.
Work sampling : for modern management
Prentice-Hall, 1960
 Buku Teks SO