Raymond P. Guiteras, David I. Levine, Stephen P. Luby, Thomas H. Polley, Kaniz Khatun-e-Jannat, Leanne Unicomb Journal of the Association of Environmental and Resource Economists 3(2), 321-3592016,
Fred A. Johnson , Paul L. Fackler , G. Scott Boomer , Guthrie S. Zimmerman , Byron K. Williams , James D. Nichols , Robert M. Dorazio PLoS ONE 11(6)2016,