1. F.V. Lenel; in “The Physics of Powder Metallurgy”, ed. W. Kingston, McGrow-Hill Book Company, New York (1951) 238.
2. H.S. Cannon and F.V. Lenel; 1. Planseeseminar, Metallwerk Plansee, Reutte (1953) 106.
3. W.A. Kaysser; Ph.D. Thesis, University Stuttgart (1978).
4. H.E. Exner; “Grundlagen von Sintervorgängen”, Gebr. Bornträger, Berlin und Stuttgart (1978).
5. W.A. Kaysser, S. Takajo and G. Petzow; “Modern Development in Powder Metallurgy”, MPIF/APMI, 12–14 (1980).