Introduction -- On the Works of Professor Koji Okuguchi -- Cournot, a Non-strategic Economist.-Cournot Tatonnement in Aggregative Games with Monotone Best Responses -- Existence and Uniqueness of Nash Equilibrium in Aggregative Games: an Expository Treatment -- On the Geometric Structure of the Cournot Equilibrium Set: the Case of Concave Industry Revenue and Convex Costs -- Pure Strategy Equilibria in Finite Symmetric Concave Games and an Application to Symmetric Discrete Cournot Games -- On a Discontinuous Cournot Oligopoly -- Interpreting Markups in Spanish Manufacturing: the Exponential Model -- Privatization Neutrality Theorem and Discriminatory Subsidy Policy -- Cournot Oligopoly Theory for Simple Electricity Markets -- Kant-Nash Equilibria in a Quantity-Setting Oligopoly -- Evolutionary Oligopoly Models of Commercial Fishing with Heterogeneities -- Existence, Uniqueness, and Comparative Statics in Contests -- Two-Group Contests with Communication Within and Between Groups -- On the Nash Equilibrium of Asymmetric Public-Good Contests -- Heterogeneity and Number of Players in Rent-Seeking, Innovation, and Patent-Race Games.