Due to the new VAT rules I have removed my digital patterns from Etsy and Craftsy, where they were illegally available to EU customers (putting me at risk of future litigation). If you are in the EU, VAT-compliant sellers Ravelry and LoveKnitting both carry my patterns, as you will see in the links.
These are standalone patterns, released independently of any book or collection.
These patterns are available in Parallax, my eBook of op-art patterns.
These patterns are available in my first book, entitled "Extreme Double-Knitting: New Adventures in Reversible Colorwork", available in print and/or PDF eBook from Cooperative Press.
Some of them are available as standalone patterns as well, if you're wanting to get just one.
These are contract designs, available only through specific outlets such as other books, magazines, clubs, etc. I do not own the rights to these patterns anymore, so please don't ask for copies if you can't or don't want to get your hands on them through the paths I describe.