A periodical is a regularly published magazine, newsletter, or journal. Several valuable periodicals concerning Switzerland genealogical research exist. Many genealogical and historical societies publish magazines and newsletters. The articles in these periodicals often include the following: | A periodical is a regularly published magazine, newsletter, or journal. Several valuable periodicals concerning Switzerland genealogical research exist. Many genealogical and historical societies publish magazines and newsletters. The articles in these periodicals often include the following: |