Issued by Letraset as dry-transfer type in 1972. No good digital version available yet.
The 5th revised edition (1976) of Lettera 2 (but not the original 1961 edition) shows a nearly identical alphabet as “Fancy Letter (1957)” and credits the design to Walter Haettenschweiler. Differences in ‘C’ and ‘E’ (ball terminals on both ends) as well as ‘Y’ (no top serif). “I don’t remember exactly where I found some existing letters. I then completed them into a full alphabet.” — W. Haettenschweiler, Swiss Type Design.