The labor-time expended by each worker would correspond to labor credits, which would be used as a currency to acquire goods and services. Market socialists that base their models on neoclassical economics, and thus marginal utility, such as Oskar Lange and Abba Lerner, have proposed that publicly owned enterprises set their price to equal marginal cost, thereby achieving pareto efficiency. Anarcho-communism as defended by Peter Kropotkin and Errico Malatesta rejected the labor theory of value and exchange value itself, advocated a gift economy and to base distribution on need.[32]