Links:
http://en.wikipedia.org/wiki/Alnus_glutinosa
http://asminhasplantas.blogspot.com/2007/09/blog-post_4626.html
http://www.jb.utad.pt/pt/herbario/cons_reg_todos1.asp?ID=837
http://arvoresdeportugal.free.fr/IndexArborium/Ficha%20AmieiroAlnusglutinosa.htm
