1. Bender, R. J., Handbook of Foamed Plastics, Libertyville, IL: Lake Publishing Company, 1965.
2. Plastics Machinery and Equipment;PA DiPierro,1982
3. Plastics Machinery and Equipment;JH DuBois,1974
4. Plastics Machinery and Equipment;JH DuBois,1975
5. Plastics Machinery and Equipment,1984