There are many governmental or non-profit or for-profit research institutes in economics or finance. I see working papers and discussion papers which were cited many times. Although 3-4 years passed, the authors probably did not consider publishing it in a journal. So, what makes a "working paper" a "completed paper" ? Without publishing it in a journal how can we know that it is really an incomplete piece of work or actually complete work but has to be named as "working paper" because of the "environment that paper available" Is it possible to have a "final draft of working paper" without publishing it in a journal?