diff --git a/schemas/styles/csl-choose.rnc b/schemas/styles/csl-choose.rnc
index 7128ebb2..57cdd5e0 100644
--- a/schemas/styles/csl-choose.rnc
+++ b/schemas/styles/csl-choose.rnc
@@ -11,8 +11,8 @@ div {
   
   ## When specifying conditions, we allow either the attribute syntax or the element-based one.
   choose.condition =
-    (condition.atts, match?)
-    | element cs:conditions { match?, condition.elem+ }
+    (condition.atts, relation, match?)
+    | element cs:conditions { match?, relation, condition.elem+ }
   choose.if = element cs:if { choose.condition, rendering-element* }
   choose.else-if =
     element cs:else-if { choose.condition, rendering-element* }
@@ -20,7 +20,8 @@ div {
   
   ## This element allows for more complex conditional logic; for 
   ## example, if you need to specify mixed "match" rules.
-  condition.elem = element cs:condition { match?, condition.atts }
+  condition.elem =
+    element cs:condition { match?, relation, condition.atts }
   condition.atts =
     (condition.atts.simple+, condition.atts.complex?)
     | condition.atts.complex
@@ -30,6 +31,11 @@ div {
     ## otherwise identical citations. This attempt at disambiguation is only
     ## made after all other disambiguation methods have failed.
     [ a:defaultValue = "true" ] attribute disambiguate { "true" }
+    | 
+      ## Tests whether the item has the given relation.
+      attribute has-relation {
+        list { relations+ }
+      }
     | 
       ## Tests whether the given variables contain numeric text.
       attribute is-numeric {
diff --git a/schemas/styles/csl.rnc b/schemas/styles/csl.rnc
index a81acee5..72324cc9 100644
--- a/schemas/styles/csl.rnc
+++ b/schemas/styles/csl.rnc
@@ -414,6 +414,7 @@ div {
     attribute variable {
       list { variables.names+ }
     },
+    relation,
     affixes,
     
     ## Specify the delimiter for name lists of name variables rendered by
@@ -690,6 +691,7 @@ div {
         date.form,
         rendering-element.date.date-part.localized*)
        | (rendering-element.date.date-part.non-localized+, delimiter)),
+      relation,
       affixes,
       display,
       font-formatting,
@@ -777,10 +779,12 @@ div {
       ## Specify verbatim text.
       attribute value { text }
     | ((attribute variable { variables.numbers | variables.strings },
-        [ a:defaultValue = "long" ] attribute form { "short" | "long" })
+        [ a:defaultValue = "long" ] attribute form { "short" | "long" },
+        relation)
        | (attribute variable { variables.titles },
           [ a:defaultValue = "long" ]
-          attribute form { "short" | "long" | "sub" | "main" })?)
+          attribute form { "short" | "long" | "sub" | "main" },
+          relation)?)
 }
 # ==============================================================================
 
@@ -803,7 +807,10 @@ div {
     ## Number forms: "numeric" ("4"), "ordinal" ("4th"), "long-ordinal"
     ## ("fourth"), "roman" ("iv").
     [ a:defaultValue = "numeric" ]
-    attribute form { "numeric" | "ordinal" | "long-ordinal" | "roman" }?
+    attribute form {
+      "numeric" | "ordinal" | "long-ordinal" | "roman"
+    }?,
+    relation
 }
 # ==============================================================================
 
@@ -846,7 +853,8 @@ div {
       delimiter,
       display,
       font-formatting,
-      rendering-element+
+      rendering-element+,
+      relation
     }
   group.attributes = notAllowed?
 }
@@ -1136,6 +1144,12 @@ div {
   always-render = attribute always-render { xsd:boolean }?
 }
 
+## Select a related-variable
+div {
+  relation = attribute relation { relations }?
+  relations = "original" | "reviewed"
+}
+
 ## Formatting attributes.
 div {
   affixes =