https://www.ana.pt/sites/default/files/documents/ana_rgc_2020_pt_website_0.pdf
https://www.mun-montijo.pt/cmmontijo/uploads/document/file/4232/Ata_n.__13.pdf
https://www.essential-business.pt/2020/04/10/fresh-doubts-shed-on-montijo-airport-plan/