From the website:

Elizabeth Zimmermann knitted the prototype for the arch shaped stockings in the 1960s. They are quite sensuous as you slip them on and feel the arch snug up into the bottom of your foot. In a thorough search of EZ’s knitting journals, no notes about this particular design were found. Meg Swansen pored over the original stockings to create the written pattern. Detailed instructions for a pair of aran or two color stockings with charts for 7 different designs including an elegant Bavarian Twisted Stitch design