APA (7th ed.) Citation
Spets, S. (2013). Programming Drupal 7 entities. Packt Pub..
Chicago Style (17th ed.) Citation
Spets, Sammy. Programming Drupal 7 Entities. Birmingham: Packt Pub., 2013.
MLA (9th ed.) Citation
Spets, Sammy. Programming Drupal 7 Entities. Packt Pub., 2013.
Warning: These citations may not always be 100% accurate.