http://books.google.pt/books?id=kpf95D8_NYcC&printsec=frontcover&dq=azeite+oliveira+cultivo&hl=pt-PT&sa=X&ei=FbD2UJzPN5KwhAePpYCgAg&ved=0CDQQ6wEwAA#v=onepage&q=azeite%20oliveira%20cultivo&f=false
http://comum.rcaap.pt/bitstream/123456789/3979/1/Olival%20em%20Modo%20de%20Produ%C3%A7%C3%A3o%20Biol%C3%B3gico.pdf
http://www.drapc.min-agricultura.pt/base/documentos/prodi_olival_2ed.pdf