Gottner, H. R. (1968). On The Planning Method "PERT" and its Application in the GDR. The Institute of National Planning.
Chicago-viite (17. p.)Gottner, Habil Reinhard. On The Planning Method "PERT" and Its Application in the GDR. Cairo: The Institute of National Planning, 1968.
MLA-viite (9. p.)Gottner, Habil Reinhard. On The Planning Method "PERT" and Its Application in the GDR. The Institute of National Planning, 1968.
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