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diff --git a/cps_and_continuation_operators.mdwn b/cps_and_continuation_operators.mdwn
index fadd34d3..6d98f645 100644
--- a/cps_and_continuation_operators.mdwn
+++ b/cps_and_continuation_operators.mdwn
@@ -357,10 +357,10 @@ Here is the hardest example. Try to figure out what this function does:
 	                     ; is this the only case where walk returns a non-atom?
 	                     [(null? l) '()]
 	                     [(atom? (car l)) (begin
-	                                        (let/cc k2
+	                                        (let/cc k2 (begin
 	                                          (set! resume k2) ; now what will happen when resume is called?
 	                                          ; when the next line is executed, what will yield be bound to?
-	                                          (yield (car l)))
+	                                          (yield (car l))))
 	                                        ; when will the next line be executed?
 	                                        (walk (cdr l)))]
 	                     [else (begin
@@ -368,10 +368,10 @@ Here is the hardest example. Try to figure out what this function does:
 	                             (walk (car l))
 	                             (walk (cdr l)))]))]
 	           [next (lambda () ; next is a thunk
-	                   (let/cc k3
+	                   (let/cc k3 (begin
 	                     (set! yield k3) ; now what will happen when yield is called?
 	                     ; when the next line is executed, what will resume be bound to?
-	                     (resume 'blah)))]
+	                     (resume 'blah))))]
 	           [check (lambda (prev)
 	                    (let ([n (next)])
 	                      (cond
@@ -380,11 +380,11 @@ Here is the hardest example. Try to figure out what this function does:
 	                        ; when will n fail to be an atom?
 	                        [else #f])))])
 	    (lambda (lst)
-	      (let ([fst (let/cc k1
+	      (let ([fst (let/cc k1 (begin
 	                   (set! yield k1) ; now what will happen when yield is called?
 	                   (walk lst)
 	                   ; when will the next line be executed?
-	                   (yield '()))])
+	                   (yield '())))])
 	        (cond
 	          [(atom? fst) (check fst)]
 	          ; when will fst fail to be an atom?
@@ -397,11 +397,13 @@ Here is [the answer](/hints/cps_hint_4), but again, first try to figure it out f
 Delimited control operators
 ===========================
 
-Here again is the CPS for `callcc`:
+Here again is the CPS transform for `callcc`:
 
  	[callcc (\k. body)] = \outk. (\k. [body] outk) (\v localk. outk v)
 
-`callcc` is what's known as an *undelimited control operator*. That is, the continuations `outk` that get bound into our `k`s include all the code from the `call/cc ...` out to *and including* the end of the program. Calling such a continuation will never return any value to the call site. (See the technique employed in the `delta` example above, with the `(begin (let/cc k2 ...) ...)`, for a work-around.)
+`callcc` is what's known as an *undelimited control operator*. That is, the continuations `outk` that get bound into our `k`s include all the code from the `call/cc ...` out to *and including* the end of the program. Calling such a continuation will never return any value to the call site.
+
+(See the technique employed in the `delta` example above, with the `(begin (let/cc k2 ...) ...)`, for a work-around. Also. if you've got a copy of *The Seasoned Schemer*, see the comparison of let/cc vs. "collector-using" (that is, partly CPS) functions at pp. 155-164.)
 
 Often times it's more useful to use a different pattern, where we instead capture only the code from the invocation of our control operator out to a certain boundary, not including the end of the program. These are called *delimited control operators*. A variety of these have been formulated. The most well-behaved from where we're coming from is the pair `reset` and `shift`. `reset` sets the boundary, and `shift` binds the continuation from the position where it's invoked out to that boundary.