Não informado. (2009). Main Science and Technology Indicators. Organization for Economic Co-operation and Development.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Main Science and Technology Indicators. Paris: Organization for Economic Co-operation and Development, 2009.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Main Science and Technology Indicators. Organization for Economic Co-operation and Development, 2009.
Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.