add reference to README

Author: Andros-Spica

README.md

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 Agent-based model representing the competition for land between stakeholders of farming and herding.
 
 
-This Agent-Based model intends to explore the conditions for the emergence and change of land use patterns in Central Asian oases and similar contexts. Land use pattern is conceptualized as the proportion between the area used for mobile livestock breeding (herding) and sedentary agriculture (farming). We assume that these two forms of land use interact in recurrent competitive situations, given that the land useful for both activities at the same time is limited and there is a pressure to increase them, due to demographic and/or economic growth. Implementation and simulation of the Musical Chairs model were done using Netlogo.
+This Agent-Based model intends to explore the conditions for the emergence and change of land use patterns in Central Asian oases and similar contexts. Land use pattern is conceptualized as the proportion between the area used for mobile livestock breeding (herding) and sedentary agriculture (farming). We assume that these two forms of land use interact in recurrent competitive situations, given that the land useful for both activities at the same time is limited and there is a pressure to increase them, due to demographic and/or economic growth. Implementation and simulation of the Musical Chairs model were done using Netlogo.
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+Angourakis, A., Rondelli, B., Stride, S., Rubio-Campillo, X., Balbo, A.L., Torrano, A., Martinez, V., Madella, M., Gurt, J.M., 2014. Land Use Patterns in Central Asia. Step 1: The Musical Chairs Model. J. Archaeol. Method Theory 21, 405–425. doi:10.1007/s10816-013-9197-0