Wittrock, J. (1967). Reducing seasonal unemployment in the construction industry: Methods of stabilising construction activity and employee income. Paris: O.E.C.D.
Παραπομπή Chicago StyleWittrock, Jan. Reducing Seasonal Unemployment in the Construction Industry: Methods of Stabilising Construction Activity and Employee Income. Paris: O.E.C.D, 1967.
Παραπομπή MLAWittrock, Jan. Reducing Seasonal Unemployment in the Construction Industry: Methods of Stabilising Construction Activity and Employee Income. Paris: O.E.C.D, 1967.
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