oops restore correct version of fig 9.1 (before diag). fix #263

Author: hjwp

images/apwp_0901.png

@@ -339,7 +339,7 @@ Ian Cooper, Abdullah Ariff, Jonathan Meier, Gil Gonçalves, Matthieu Choplin,
 Ben Judson, James Gregory, Łukasz Lechowicz, Clinton Roy, Vitorino Araújo,
 Susan Goodbody, Josh Harwood, Daniel Butler, Liu Haibin, Jimmy Davies, Ignacio
 Vergara Kausel, Gaia Canestrani, Renne Rocha, pedroabi, Ashia Zawaduk, Jostein
-Leira, Brandon Rhodes,
+Leira, Brandon Rhodes, Jazeps Basko 
 and many more; our apologies if we missed you on this list.
 
 Super-mega-thanks to our editor Corbin Collins for his gentle chivvying, and