1- Abdollahi S. 2008. To evaluate the prospects of development of organic farming in Iran, Tehran: Ministry of Agriculture, Department of Planning and Economic Research, Institute for Planning and Agricultural Economics. (In Persian)
2- Azizi V., Nikoy M., and Khaledi M. 2013. Market development strategies for healthy food products in Hamadan. Economic and agricultural development, 27 (4): 328-337. (In Persian)
3- Amirnejad H. 2005. The total economic value of ecosystems in forests with emphasis on bio-environment values ecological and conservation values, Ph.D. dissertation Agricultural Economics, College of Agriculture, Tarbiat Modarres University. (In Persian)
4- Boyle K. J., Johnson F. R., McCollum D. W., Desvousges W. H., and Hudson S. 1996. Valuing public goods: discrete versus continuous contingent–valuation responses. Land Economics, 72: 381–396.
5- Chaichi B. 2009. Farming healthy soil, healthy plants, healthy. Monthly livestock, agro-industry, 117: 39-50. (in Persian)
6- Cooper J. C., Hanemann M., and Signorello G. 2002. One-and-one-half-bound dichotomous- choice contingent Valuation. The Review of Economics and Statistics, 84 (4): 742-750.
7- Creel M., and Loomis J. 1997. Semi-nonparametric distribution-free dichotomous choice contingent valuation. Journal of Environmental Economics and Management, 32 (3): 341-358.
8- Gallant A. R. 1982. Unbiased determination of production technologies. Journal of Econometrics, 20: 285-323.
9- Gunduz O., and Bayramoghlo Z. 2011. Consumer willingness to pay Chicken Meat in Samsun Province of Turkey. Journal of Animal and Veterinary Advances, 21(3): 331-333.
10- Hafeznia M. R. 2010. Introduction to Research in the Humanities (revised basic additions), Semat publishing, Tehran. (In Persian)
11- Hanemann W. M. 1984. Welfare evaluations in contingent valuation experiment with discrete responses. American Journal of Agriculture Economics, 71: 332-341.
12- Jafari A. 2004. The importance of varieties and investigating effective factors on their erosion (first section). Espehan Magazine, 5: 8-11.
13- Kealy J.M., and Turner R.W. 1993. A test of the equality of close-ended and open-ended contingent valuation. American Journal of Agricultural Economics, 75: 321-331.
14- Khoshakhlagh R., and Hasanshahi M. 2002. Estimated damages to the residents of Shiraz, due to air pollution (2002). Economic Research Journal, 61: 53-57. (In Persian with English abstract)
15- Kiany GH., and Liaghati H. 2007. Analysis of economic conditions become common agriculture to organic farming using dynamic linear programming model. p. 2727-2737 Proceedings of the Second National Conference on Ecological Agriculture, 17-18 October 2007, Iran, Gorgan. (In Persian)
16- Koochaki A., Nakhforosh A., and Zarifketabi H. 1997. Farming, University of Mashhad, No. 217.
17- Mafi L., and Saleh A. 2009. Estimatin of willingness to pay for organic products Case Study: vegetables, cucumbers, Agricultural Economics Conference in Iran. 7-8 May 2014. Iran, Karaj. (In Persian)
18- Marette S., Messean A., and Millet G. 2012. Consumers’ willingness to pay for eco-friendly apples under different labels: Evidences from a lab experiment. Food Policy, 37: 151-161.
19- Mitchell R., and Carson R. 1989. Using surveys to value public goods: The contingent valuation method, Washington DC, Johns Hopkins University Press for Resources for the Future.
20- Mohamadi A. 2012. Estimates of willingness to pay for organic meat product in Ahvaz. p. 1823-1836. Iran Agricultural Economics Conference. 9-10 May 2012. Iran, Shiraz. (In Persian)
21- Papzan A., and Shiri N. 2012. Farming barriers and development problems. Journal of Economics and Rural Development space, 1: 113-126. (In Persian with English abstract)
22- Saraee H. 2005. Introduction to survey sampling. Semat publishing, Tehran. (In Persian)
23- Sasouli M. R., Yazdani S., Hosseini S. S., and Saleh E. 2015. Study of social acceptance of products irrigated with treated wastewater in the south of Tehran. Iranian Journal of Agricultural Economics and Development Research. 46 (1): 1-11.
24- Van Loo E., Caputo V., Nayga R., Pieniak Z., and Verbeke W. 2013. Consumer attitudes, knowledge, and consumption of organic yogurt. American Dairy Science, 96(4):2118-2129.