diff --git a/src/ch04/s00-concerns.md b/src/ch04/s00-concerns.md
index 146cac8..1e1cc15 100644
--- a/src/ch04/s00-concerns.md
+++ b/src/ch04/s00-concerns.md
@@ -2,18 +2,18 @@
 
 ## There exist alternative `Functor` implementations
 
-See the [relevant subchapter](s01-alternatives.md)
+See the [relevant subchapter](./s01-alternatives.md)
 
 ## It might be better to have a per-lifetime trait for `Functor`s
 
-See the [relevant subchapter](s02-lifetimes.md)
+See the [relevant subchapter](./s02-lifetimes.md)
 
 ## `Stackless` is kind of bad
 
-See the [relevant subchapter](s03-stackless.md)
+See the [relevant subchapter](./s03-stackless.md)
 
 ## `WeakFunctor::F<'a, A>` is not (yet) covariant over the lifetime `'a`
 
-See the [relevant subchapter](s04-covariance.md)
+See the [relevant subchapter](./s04-covariance.md)
 
 ## Can `WeakFunctor` be an associated type of a `Functor` instead of its supertype?