Nelson AH, Hudler GW. A summary of North American hardwood tree diseases with bleeding canker symptoms. Arboriculture and Urban Forestry  [Internet]. 2007  ;33(2):122-131. Available from: http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=57&ved=0CE4QFjAGODI&url=http%3A%2F%2Fjoa.isa-arbor.com%2Frequest.asp%3FJournalID%3D1%26ArticleID%3D2985%26Type%3D2&ei=pKOvUpvjGcv7oASXoYDYDA&usg=AFQjCNHxNzEH7As_NfGpUf1LVGxbCXIeXA