حقیقت, جعفر, معصوم زاده, سارا, سیدهاشمی, فاطمه. “Covid - 19 Crisis and stock market volatility Markov switching nonlinear approach at the level of industries.” Financial Economics, vol. 19, no. 70, 2025, pp. 157-178. https://doi.org/10.71818/ecj.2025.1061999