Screen Shot 2015-10-31 at 17.51.14.png

Licence: 
Creative Commons Licence
Imaging technique: 
Illustration
Description: 

From Szymczakowski (1970)

Creator: 
W. Szymczakowski
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith