Boutayeb Nasser, Ghemima Mostefa. “The Role of Investment Spending in Boosting Non-Hydrocarbon GDP An Econometric Study for the Period 2000 2023”. European Economic Letters (EEL) 15, no. 1 (March 11, 2025): 3058–3071. Accessed July 26, 2026. https://www.eelet.org.uk/index.php/journal/article/view/2703.