- ↑Purcell and Morin, Harvard Univasity. (2013).Elektricity and Magnetism, 820p (3rd ed.). Cambridge Univasity Press, New York.ISBN 978-1-107-01402-2. p 430: "These waves... require no medium to support their propageishion. Traveling elektromagnetik waves karry enerjy, and... diPoynting vector deskraib di enerjy flow...;" p 440: ... di elektromagnetik wave must get di following propatis: 1) Di field patan dé travel with speed c (speed of laight); 2) At every point within di wave... di elektrik field strength E equals "c" taims di magnetik field strength B; 3) Di elektrik field and di magnetik field dé perpendikula to one anoda and to di dairekshion of travel, or propageishion."
