diff --git a/pkgs/development/tools/parsing/bison/bison-1.875.nix b/pkgs/development/tools/parsing/bison/bison-1.875.nix
index da124fcc474d..3ee12a252cec 100644
--- a/pkgs/development/tools/parsing/bison/bison-1.875.nix
+++ b/pkgs/development/tools/parsing/bison/bison-1.875.nix
@@ -5,7 +5,7 @@ assert m4 != null;
 stdenv.mkDerivation {
   name = "bison-1.875";
   src = fetchurl {
-    urls = mirror://gnu/bison/bison-1.875.tar.bz2;
+    url = mirror://gnu/bison/bison-1.875.tar.bz2;
     md5 = "b7f8027b249ebd4dd0cc948943a71af0";
   };
   buildInputs = [m4];