Imperfect.

Essays on value and distribution Kaldor, Nicholas 1981 Imperfect competition, differential information, and microfoundations of macroeconomics Nishimura, Kiyohiko 1992 Increasing returns and economic analysis edited by Kenneth J. Arrow, Yew-Kwang Ng, and Xiaokai Yang 1998 Kalecki's microanalysis Kriesler, Peter 1987 Market structure and foreign trade Helpman, Elhanan 1985 The economics of imperfect competition Greenhut, Melvin L. 1987 The economics of imperfect competition Robinson, Joan 1961 The Economics of imperfect competition: a spatial approach Greenhut, Melvin L. 1987 The Economics of imperfect competition and employment Author not listed 1950 The economics of imperfect competition Robinson, Joan 1969 The monopolistic competition revolution in retrospect Steven Brakman and Ben J. Heijdra, editors 2004 The theory of imperfect competition Dewey, Donald 1969