@Article{500465,
     author = "Nana Kofi Annan, Daniel Michael Okwabi Adjin, George Orleans Ofori-Dwunfou",
     title = "The m-technologies in m-learning",
     year =  2013,
     volume =  ,
     number =  105,
     journal =  Ekonomiczne Problemy Usług,
     pages =  s. 643-654,
    }