Gottner, H. R. (1968). On The Critical Path Method (C.P.M) and its Application in the G.D.R. The Institute of National Planning.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Gottner, Habil Reinhard. On The Critical Path Method (C.P.M) and Its Application in the G.D.R. Cairo: The Institute of National Planning, 1968.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Gottner, Habil Reinhard. On The Critical Path Method (C.P.M) and Its Application in the G.D.R. The Institute of National Planning, 1968.