Celko, J. (2012). Joe Celko's Trees and hierarchies in SQL for smarties (Second edition.). Elsevier/Morgan Kaufmann.
Citazione stile Chigago Style (17a edizione)Celko, Joe. Joe Celko's Trees and Hierarchies in SQL for Smarties. Second edition. Amsterdam ; Boston: Elsevier/Morgan Kaufmann, 2012.
Citatione MLA (9a ed.)Celko, Joe. Joe Celko's Trees and Hierarchies in SQL for Smarties. Second edition. Elsevier/Morgan Kaufmann, 2012.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.