As a rule, the authors of each paper are offered one printed copy of the issue containing their article. Several authors may have not chances to collect the copies, leading to an amount of backlogs available. 

If you want to get a printed version of previous issues, released since 2013 to date, please come to take at the journal's office. In case it is inconvenient to come, please email us to inform in detail your query as well as you current post address. We may send the issue (s) to you by courier service.