Economic experiments have shown that punishment can increase public goods game contributions over time. However. the effectiveness of punishment is challenged by second-order free-riding and antisocial punishment. The latter implies that noncooperators punish cooperators. https://www.chiggate.com/turbo-air-m3f72-3-n-78-wide-m3-series-reach-in-freezer-featuring-three-solid-doors-energy-star-online-now/