• http://www.ravelry.com/groups/knitting-sheaths
• http://www.ravelry.com/groups/lever-production-or-irish-cottage-knitting
• http://www.ravelry.com/groups/shetland-knitting-belts

Other Resources:

Ravelry Groups:

• Hazel Tindall's blog post with photos of old, leather knitting belts:
  
  • http://www.hazeltindall.com/knitting-belts1#.U0KTmFJwaDY
• More interesting links about knitting belts:
  • http://ayarnoverneedles.blogspot.co.uk/2012/02/makkin-knitting-belt.html
  • https://thetinfoilhatsociety.com/tag/knitting-belt/
  • http://jeanmiles.blogspot.com/2013/10/i-haveheard-from-jamieson-smith-that-my.html?m=1
  • https://www.reddit.com/r/knitting/comments/4lrfyz/thats_not_how_any_of_this_works/
  • http://www.principlesofknitting.com/wp-content/uploads/2017/07/PWK-0717.pdf