Gaya APA
      Zulkifli, A. (2020).
    Green marketing: redefinisi green product, green price, green place, dan green promotion .
    Yogyakarta:
  Graha Ilmu.
  
Gaya MLA
      Zulkifli, Arif.
    "Green marketing: redefinisi green product, green price, green place, dan green promotion".
    
    Yogyakarta:
  Graha Ilmu,
  2020.
  Text.