Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Chicken wire tessellation. Mountain folds are indicated by solid lines and valley folds by dashed lines. Fold lines of the same colour have the same fold angle. (a) Fold pattern, (b) partially folded position, and (c) pre-interference position.
