diff --git a/basis/byte-arrays/hex/authors.txt b/basis/byte-arrays/hex/authors.txt
index f13c9c1e77..8f20b8c31e 100644
--- a/basis/byte-arrays/hex/authors.txt
+++ b/basis/byte-arrays/hex/authors.txt
@@ -1 +1,2 @@
-Joe Groff
+Maxim Savchenko
+Slava Pestov
diff --git a/basis/byte-arrays/hex/hex-docs.factor b/basis/byte-arrays/hex/hex-docs.factor
index 8c60dc2646..8a2b842fc9 100644
--- a/basis/byte-arrays/hex/hex-docs.factor
+++ b/basis/byte-arrays/hex/hex-docs.factor
@@ -1,3 +1,5 @@
+! Copyright (C) 2009 Maxim Savchenko, Slava Pestov.
+! See http://factorcode.org/license.txt for BSD license.
 IN: byte-arrays.hex
 USING: byte-arrays help.markup help.syntax ;
 
diff --git a/basis/byte-arrays/hex/hex.factor b/basis/byte-arrays/hex/hex.factor
index 054c35dcfa..f1b9a52303 100644
--- a/basis/byte-arrays/hex/hex.factor
+++ b/basis/byte-arrays/hex/hex.factor
@@ -1,4 +1,4 @@
-! Copyright (C) 2009 Joe Groff.
+! Copyright (C) 2009 Maxim Savchenko, Slava Pestov.
 ! See http://factorcode.org/license.txt for BSD license.
 USING: grouping lexer ascii parser sequences kernel math.parser ;
 IN: byte-arrays.hex