http://www.youtube.com/watch?v=8PWROX0PGvY
Nieaktualne
https://www.google.com/search?q=Szyfry+(1966)+yt&client=firefox-b&source=lnms&tb m=vid&sa=X&ved=0ahUKEwi6ktm1iN_fAhXAXhUIHRO8DP0Q_AUIDygC&biw=1366&bih=613 tera winno styknąć