Structural Changes in the Impact of Covid-19 Pandemic on the Performance of Financial Markets. Stock Market by Using Least Squares WHTI BreaksIssam Djouadi، Okba Abdellaoui، Madani AbdelRahim، Debbab IbrahimFinancial Markets Institutions and Risksالمجلّد 8، (2)، الصفحات 37-492024مقال وصول مفتوح 4