@Article{312310,
     author = "Olaf Olsen",
     title = "Wydobycie i odnawianie pięciu drakkarów ",
     year =  1970,
     volume =  15,
     number =  1,
     journal =  Kwartalnik Historii Nauki i Techniki,
     pages =  s. 233-235,
    }