Gaya APA
      O'Connor, J. et al (2004).
    Electronic Marketing Theory and Practice for the Twenty-first Century .
    England:
  prentice hall financial times.
  
Gaya MLA
      O'Connor, John. et al.
    "Electronic Marketing Theory and Practice for the Twenty-first Century".
    
    England:
  prentice hall financial times,
  2004.
  Text.