Index: doc/theses/aaron_moss_PhD/phd/type-environment.tex
===================================================================
--- doc/theses/aaron_moss_PhD/phd/type-environment.tex	(revision 70eaa80b0f07a23246e87e901379056e4542937b)
+++ doc/theses/aaron_moss_PhD/phd/type-environment.tex	(revision 6eed619c3a4823cae4e1aa0fece8eb1c0cbcc591)
@@ -299,3 +299,6 @@
 This persistent union-find data structure is efficient, but not thread-safe; as suggested in Section~\ref{resn-conclusion-sec}, it may be valuable to parallelize the \CFA{} expression resolver. 
 However, allowing multiple threads concurrent access to the persistent data structure is likely to result in ``reroot thrashing'', as different threads reroot the data structure to their own versions of interest. 
-This contention could be mitigated by partitioning the data structure into separate subtrees for each thread, with each subtree having its own root node, and the boundaries among them implemented with a lock-equipped !ThreadBoundary! edit node.
+This contention could be mitigated by partitioning the data structure into separate subtrees for each thread, with each subtree having its own root node, and the boundaries among them implemented with a lock-equipped !ThreadBoundary! edit node. 
+\cbstartx
+Alternatively, the concurrent hash trie of Prokopec \etal{} \cite{Prokopec11,Prokopec12} may be a useful hash-table replacement.
+\cbendx