APA-viite (7. p.)
Butcher, M. (2008). Learning Drupal 6 module development: A practical tutorial for creating your first Drupal 6 modules with PHP. Packt.
Chicago-viite (17. p.)
Butcher, Matt. Learning Drupal 6 Module Development: A Practical Tutorial for Creating Your First Drupal 6 Modules with PHP. Birmingham: Packt, 2008.
MLA-viite (9. p.)
Butcher, Matt. Learning Drupal 6 Module Development: A Practical Tutorial for Creating Your First Drupal 6 Modules with PHP. Packt, 2008.
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