Refrensi :
http://more-examples.blogspot.co.id/2012/11/elemen-yang-digunakan-dalam-diagram.html
http://repository.petra.ac.id/15653/1/BPMN-UML.pdf
https://www.academia.edu/4758904/Business_Process_Modeling_Notation_BPMN_Introducing_Business_Process_Analysis
http://www.enciety.com/web/news.php?act=detail&n_id=60