Bibliography (9):

1. Clarifying the Structure and Nature of Left-Wing Authoritarianism (LWA)

2. Poor Prospects—Not Inequality—Motivate Political Violence

3. Conspiracy mentality and political orientation across 26 countries

4. Individual-Level Cognitive and Personality Predictors of Ideological Worldviews: The Psychological Profiles of Political, Nationalistic, Dogmatic, Religious, and Extreme Believers

5. Mass Shootings: Definitions and Trends

6. Wikipedia Bibliography:

   1. September 11 attacks

   2. https://en.wikipedia.org/wiki/Islamic_terrorism  :

      https://en.wikipedia.org/wiki/Islamic_terrorism

   3. https://en.wikipedia.org/wiki/Al-Qaeda  :

      https://en.wikipedia.org/wiki/Al-Qaeda

   4. Islamic State