diff --git a/relational-record.cabal b/relational-record.cabal
--- a/relational-record.cabal
+++ b/relational-record.cabal
@@ -1,5 +1,5 @@
 name:                relational-record
-version:             0.1.5.1
+version:             0.1.6.0
 synopsis:            Meta package of Relational Record
 description:         Meta package to install Relational Record quickly
 homepage:            http://khibino.github.io/haskell-relational-record/
diff --git a/src/Database/Relational/Query/Documentation.hs b/src/Database/Relational/Query/Documentation.hs
--- a/src/Database/Relational/Query/Documentation.hs
+++ b/src/Database/Relational/Query/Documentation.hs
@@ -1,6 +1,6 @@
 -- |
 -- Module      : Database.Relational.Query.Documentation
--- Copyright   : 2014-2016 Kei Hibino
+-- Copyright   : 2014-2017 Kei Hibino
 -- License     : BSD3
 --
 -- Maintainer  : ex8k.hibino@gmail.com
@@ -40,6 +40,8 @@
   inner, left, right, full,
   on',
 
+  JoinRestriction,
+
   -- *** Finalize Context
   -- $finalize
   Relation,
@@ -227,6 +229,7 @@
 'inner', 'left', 'right', 'full' operators can construct join products directly like SQL.
 'inner' operator is INNER JOIN of SQL, 'left' operator is LEFT OUTER JOIN of SQL, and so on.
 'on'' operator specifies condition of join product.
+'JoinRestriction' is the type of lambda form which expresses condition of join product.
  -}
 
 {- $finalize