+These notes may change in the next few days (today is 30 Nov 2010).
+The material here benefited from many discussions with Ken Shan.
-##[[Zipper]]##
+##[[Tree and List Zippers]]##
-##[[Continuations]]##
+##[[Coroutines and Aborts]]##
+
+##[[From List Zippers to Continuations]]##
+
+continue with [[Week12]]...