1. The Swedish Association of Pellet Producers (PiR). Statistik om pellets i Sverige. [Statistics concerning wood fuel pellets in Sweden]. http://www.pelletsindustrin.org/page/1/36.html. Stockholm, Sweden. 2006-09-12 (in Swedish).
2. Karlsson I. Att göra pellets attraktivt för fler. [Making the use of pellets more attractive for more people]. Oral presentation. Pellets 07 Conference, 30–31 January. Örebro Sweden. 2007-01-31 (in Swedish).
3. Implementation and application of Quality Assurance systems;Langheinrich;Biomass and Bioenergy,2006
4. Stigson B. Strategies for energy and environment—what can standards do? Oral presentation. World Business Council for Sustainable Development—Global responsibility. http://www.iso.org. Stockholm, Sweden. 2002-09-25.
5. SS 187120. Biobränslen och torv—Bränslepellets—Klassificering. (Biofuels and peat—Fuel pellets—Classification). Swedish Standards Institute (SIS). Stockholm, Sweden. 3 pp. 1998–06-10 (in Swedish).