Several patterns are used to pave the surface following a given lattice (same translations, but the lattices might be shifted between two patterns); we can see that the nodes are corresponding, i.e. the pavements are equivalent ; the picture shows that the definition of a cell is not unique
Christophe Dang Ngoc Chan (<a href="//commons.wikimedia.org/wiki/User:Cdang" title="User:Cdang">cdang</a>)
CC BY-SA 3.0
<span class="int-own-work" lang="en">Own work</span>