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diff --git a/topics/week3_lists.mdwn b/topics/week3_lists.mdwn
index 14663cda..08b35162 100644
--- a/topics/week3_lists.mdwn
+++ b/topics/week3_lists.mdwn
@@ -1,5 +1,6 @@
 # More on Lists #
 
+<a id=comprehensions></a>
 ## Comprehensions ##
 
 We know you are already familiar with the following kind of notation for designating sets:
@@ -48,7 +49,7 @@ Haskell also has an extension that permits you to iterate over multiple lists *i
 
     [ 10*x + y | y <- [4, 5, 6] | x <- [1, 2, 3] ]
 
-will evaluate to `[14, 25, 36]`. If the lists are of unequal length, Haskell stops when it exhausts the first. These behaviors are similar to the `map2` function you defined in the week 1 homework. That also took an argument from each of several sequences in parallel. (The corresponding functions in Haskell are called `zip` and `zipWith`.)
+will evaluate to `[14, 25, 36]`. If the lists are of unequal length, Haskell stops when it exhausts the shortest. These behaviors are similar to the `map2` function you defined in the week 1 homework. That also took an argument from each of several sequences in parallel. (The corresponding functions in Haskell are called `zip` and `zipWith`.)
 
 OCaml [permits lists comprehensions as an extension](http://stackoverflow.com/questions/27652428/list-comprehension-in-ocaml), and [so too does Scheme](http://srfi.schemers.org/srfi-42/srfi-42.html), but these are a bit harder to use.
 
@@ -119,6 +120,8 @@ not to:
 To get the latter, you'd need to apply `join` twice.
 
 
+
+<a id=tails></a>
 ## Tails ##
 
 For the Lambda Calculus, we've proposed to encode lists in terms of higher-order functions that perform right-folds on (what we intuitively regard as) the real list. Thus, the list we'd write in Kapulet or Haskell as:
@@ -151,3 +154,5 @@ Try it out in the lambda evaluator. After the code above, you can write:
 
 and the result will be `\f z. f b (f c z)`, our encoding of `[b, c]`.
 
+
+<a id=v2-lists></a>