diff --git a/networks.rkt b/networks.rkt
index 2e53707..65b40fd 100644
--- a/networks.rkt
+++ b/networks.rkt
@@ -89,12 +89,12 @@
 
 ;;; Build an update function from an update function form.
 (define (update-function-form->update-function form)
-  (lambda (s) (eval-with s form)))
+  (λ (s) (eval-with s form)))
 
 ;;; Build a network from a network form.
 (define (network-form->network bnf)
   (make-hash
-   (hash-map bnf (lambda (x form)
+   (hash-map bnf (λ (x form)
                    (cons x (update-function-form->update-function form))))))
 
 ;;; Build a network from a list of pairs of forms of update functions.
diff --git a/utils.rkt b/utils.rkt
index 18787db..8acba00 100644
--- a/utils.rkt
+++ b/utils.rkt
@@ -120,7 +120,7 @@
 ;;;
 (define (eval-with ht expr)
   (parameterize ([current-namespace (make-base-namespace)])
-    (hash-for-each ht (lambda (x val)
+    (hash-for-each ht (λ (x val)
                         (namespace-set-variable-value! x val)))
     (eval expr)))