.onAttach <- function(...) {
  packageStartupMessage("

  To cite package SetMethods in publications use: 

  Oana, Ioana-Elena and Carsten Q. Schneider. 2018. SetMethods: An Add-on R Package for 
  Advanced QCA. The R Journal 10(1): 507-33. https://journal.r-project.org/archive/2018/RJ-2018-031/index.html
  
  ")
}