diff --git a/preserves-binary.md b/preserves-binary.md
index 3bc3371..ddae30c 100644
--- a/preserves-binary.md
+++ b/preserves-binary.md
@@ -6,12 +6,8 @@ title: "Preserves: Binary Syntax"
 Tony Garnock-Jones <tonyg@leastfixedpoint.com>  
 {{ site.version_date }}. Version {{ site.version }}.
 
-  [sexp.txt]: http://people.csail.mit.edu/rivest/Sexp.txt
-  [spki]: http://world.std.com/~cme/html/spki.html
   [varint]: https://developers.google.com/protocol-buffers/docs/encoding#varints
   [LEB128]: https://en.wikipedia.org/wiki/LEB128
-  [erlang-map]: http://erlang.org/doc/reference_manual/data_types.html#map
-  [abnf]: https://tools.ietf.org/html/rfc7405
   [canonical]: canonical-binary.html
 
 *Preserves* is a data model, with associated serialization formats. This
diff --git a/preserves-text.md b/preserves-text.md
index 258f4f2..e6a77c0 100644
--- a/preserves-text.md
+++ b/preserves-text.md
@@ -7,12 +7,7 @@ Tony Garnock-Jones <tonyg@leastfixedpoint.com>
 {{ site.version_date }}. Version {{ site.version }}.
 
   [sexp.txt]: http://people.csail.mit.edu/rivest/Sexp.txt
-  [spki]: http://world.std.com/~cme/html/spki.html
-  [varint]: https://developers.google.com/protocol-buffers/docs/encoding#varints
-  [LEB128]: https://en.wikipedia.org/wiki/LEB128
-  [erlang-map]: http://erlang.org/doc/reference_manual/data_types.html#map
   [abnf]: https://tools.ietf.org/html/rfc7405
-  [canonical]: canonical-binary.html
 
 *Preserves* is a data model, with associated serialization formats. This
 document defines one of those formats: a textual syntax for `Value`s
diff --git a/preserves.md b/preserves.md
index aff94aa..3132d96 100644
--- a/preserves.md
+++ b/preserves.md
@@ -6,14 +6,6 @@ title: "Preserves: an Expressive Data Language"
 Tony Garnock-Jones <tonyg@leastfixedpoint.com>  
 {{ site.version_date }}. Version {{ site.version }}.
 
-  [sexp.txt]: http://people.csail.mit.edu/rivest/Sexp.txt
-  [spki]: http://world.std.com/~cme/html/spki.html
-  [varint]: https://developers.google.com/protocol-buffers/docs/encoding#varints
-  [LEB128]: https://en.wikipedia.org/wiki/LEB128
-  [erlang-map]: http://erlang.org/doc/reference_manual/data_types.html#map
-  [abnf]: https://tools.ietf.org/html/rfc7405
-  [canonical]: canonical-binary.html
-
 *Preserves* is a data model, with associated serialization formats.
 
 It supports *records* with user-defined *labels*, embedded *references*,