References

[1] Syncdir, http://syncdir.sourceforge.com/ [2] Best free backup software: http://www.in.techradar.com/ news/software/applications/Best-free-backup-software-11programs-we-recommend/articleshow/38877922.cms [3] 13 Best backup software: http://www.pcadvisor.co.uk/ test-centre/software/13-best-backup-software-2015-2016uk-3263573/