--- a/pnas/pnas.tex	Wed Nov 17 11:58:35 2010 -0800
+++ b/pnas/pnas.tex	Wed Nov 17 15:24:09 2010 -0800
@@ -204,8 +204,7 @@
 
 One approach to such a generalization might be to simply define a
 TQFT via its gluing formulas, replacing tensor products with
-derived tensor products.
-\nn{maybe cite Kh's paper on links in $S^1\times S^2$}
+derived tensor products (c.f. \cite{1011.1958}).
 However, it is probably difficult to prove
 the invariance of such a definition, as the object associated to a manifold
 will a priori depend on the explicit presentation used to apply the gluing formulas.