@Article{397139,
     author = "Tadeusz Mazur",
     title = "The Level of Births and Deaths in the Lublin Province in 1867-1912",
     year =  1984,
     volume =  18,
     number =  ,
     journal =  Annales Universitatis Mariae Curie-Skłodowska. Sectio H, Oeconomia,
     pages =  s. 233-254,
    }