1. Allen, E. 1996. Decay and wood utilization problems in red alder and paper birch. In Proceedings of Ecology and Management of B.C. Hardwoods Workshop, Richmond, B.C., December 1–2, 1993. Edited by P.G. Comeau, G.J. Harper, M.E. Blach, J.O. Boateng, and D.T. Keith. Ministry of Forests, Victoria, B.C. pp. 139–146.
2. Basham, J.T. 1991. Stem decay in living trees in Ontario's forest: a user's compendium and guide. Can. For. Serv. Gt. Lakes For. Cent. Inf. Rep. O-X-408.
3. Boulet, B. 2005. Défauts externes et indices de la carie des arbres: guide d'interprétation. Publications du Québec, Quebec City, Que.
4. Cole, W.G. 1995. Hardwood tree crown measurement guide. Ministry of Natural Resources, Ontario Forest Research Institute, Sault-Ste. Marie, Ont.