citHeader("When citing cdlTools, please cite both the package and underlying data sources used:")

citEntry(entry = "Manual",
         author = personList(
           as.person("Lu Chen"),
           as.person("Jonathan Lisic")),
         title = "Tools to Download and Work with USDA Cropscape Data",
         year = "2018",
         url = "https://cran.r-project.org/package=cdlTools",
         textVersion = paste("Chen, L., Lisic, J. (2018). Tools to Download and Work with USDA Cropscape Data. R package version 0.14. https://cran.r-project.org/package=cdlTools"))

citEntry(entry = "Manual",
         author = "USDA-NASS",
         title = "National Agricultural Statistics Service Cropland Data Layer",
         year = "2019",
         url = "https://nassgeodata.gmu.edu/CropScape/",
         textVersion = paste("USDA-NASS. (2019) National Agricultural Statistics Service Cropland Data Layer. https://nassgeodata.gmu.edu/CropScape/"))
