diff --git a/readme.markdown b/readme.markdown
index 5e1aea33..0eb16d7f 100644
--- a/readme.markdown
+++ b/readme.markdown
@@ -225,10 +225,6 @@ default `opts` values:
 }
 ```
 
-## resolve.isCore(pkg)
-
-Return whether a package is in core.
-
 # install
 
 With [npm](https://npmjs.org) do: