INCOSE Lean Enablers for Systems Engineering
Lean Systems Engineering Working Group. 2009. "Lean Enablers for Systems Engineering." (presentation) Accessed 9 March 2015 at http://www.acq.osd.mil/se/webinars/2010-05-04-SECIE-Lean-Enablers-for-SE-Oppenheim-brief.pdf
This source is considered a primary reference for the Lean Engineering article.
The full text of this source is available at http://cse.lmu.edu/Assets/Colleges+Schools/CSE/Lean+Enablers+for+SE+Version+1.01.pdf. Please note that this source is a presentation on lean enablers; it is different from the document Lean Enablers for Systems Engineering.