Fix 236--239.

1 files changed, 5 insertions, 4 deletions

diff --git a/sec/systemt.ltx b/sec/systemt.ltx
index 75461f9..c43223e 100644
--- a/sec/systemt.ltx
+++ b/sec/systemt.ltx
@@ -302,10 +302,11 @@ reconstruct both folds and pattern matching.
 
 \subsubsection*{Heap Encodings}
 
-This encoding strategy is a crude approximation of a heap of memory. Given an
-indexing type \(I\), an inductive type is a triple of a \emph{recursive depth},
-a \emph{root index}, and an \(I\)-indexed \emph{heap} of values. Instead of
-storing recursive values ``in-line'', one stores an index to its place in the heap.
+This encoding strategy is a crude approximation of a heap of
+memory~\cite{heap}. Given an indexing type \(I\), an inductive type is
+a triple of a \emph{recursive depth}, a \emph{root index}, and an
+\(I\)-indexed \emph{heap} of values. Instead of storing recursive
+values ``in-line'', one stores an index to its place in the heap.
 
 Consider the binary tree
 \(\mathsf{branch}(\mathsf{branch}(\mathsf{leaf}(1), \mathsf{leaf}(2)),