1. Brochure forDREF 3 Friction Spinning Machine (Textilmaschinenfabrik, Dr. Ernst Fehrer A G).
2. H. Fuchs,Textile Horizons,2, 20 (1982).
3. K. J. Brockmanns and J. Lunenschloss,ITB International Textile Bulletin,30, 5 (1984).
4. M. Gsteu,Textile Horizons,6, 36 (1986).
5. M. Gsteu,ITB International Textile Bulletin,32, 65 (1986).