@TECHREPORT{Var_Pro_2016, author = "Vargas Guzman, Jose Antonio", title = "Proyecto de la tierra", year = 2016, institution = "Repositorio CorporaciĆ³n Unificada Nacional de EducaciĆ³n Superior", url = "https://repositorio.cun.edu.co/handle/cun/2659", }