diff --git a/generated_files/g7validation.json b/generated_files/g7validation.json
index e493b02..53cab2e 100644
--- a/generated_files/g7validation.json
+++ b/generated_files/g7validation.json
@@ -745,6 +745,12 @@
     },
     "https://gedcom.io/terms/v7/record-SUBM": {
       "en-US": "Submitter"
+    },
+    "https://github.com/dthaler/gedcom-citations/_DATE": {
+      "en-US": "Date"
+    },
+    "https://github.com/dthaler/gedcom-citations/_SOUR": {
+      "en-US": "Source"
     }
   },
   "payload": {
@@ -7640,7 +7646,9 @@
     "https://gedcom.io/terms/v7/record-REPO": "REPO",
     "https://gedcom.io/terms/v7/record-SNOTE": "SNOTE",
     "https://gedcom.io/terms/v7/record-SOUR": "SOUR",
-    "https://gedcom.io/terms/v7/record-SUBM": "SUBM"
+    "https://gedcom.io/terms/v7/record-SUBM": "SUBM",
+    "https://github.com/dthaler/gedcom-citations/_DATE": "_DATE",
+    "https://github.com/dthaler/gedcom-citations/_SOUR": "_SOUR"
   },
   "tagInContext": {
     "cal": {
diff --git a/generated_files/registry_path.tsv b/generated_files/registry_path.tsv
index 202e198..f4427c9 100644
--- a/generated_files/registry_path.tsv
+++ b/generated_files/registry_path.tsv
@@ -314,5 +314,5 @@ https://gedcom.io/terms/v7/type-FilePath	data-type/standard/type-FilePath.yaml
 https://gedcom.io/terms/v7/type-List	data-type/standard/type-List.yaml
 https://gedcom.io/terms/v7/type-Name	data-type/standard/type-Name.yaml
 https://gedcom.io/terms/v7/type-Time	data-type/standard/type-Time.yaml
-https://github.com/dthaler/gedcom-citations/_DATE	structure/extension/_DATE
-https://github.com/dthaler/gedcom-citations/_SOUR	structure/extension/_SOUR
+https://github.com/dthaler/gedcom-citations/_DATE	structure/extension/_DATE.yaml
+https://github.com/dthaler/gedcom-citations/_SOUR	structure/extension/_SOUR.yaml
diff --git a/structure/standard/MEDI.yaml b/structure/standard/MEDI.yaml
index b8dd74d..5eda585 100644
--- a/structure/standard/MEDI.yaml
+++ b/structure/standard/MEDI.yaml
@@ -26,6 +26,16 @@ specification:
     rather than `BOOK` or `NEWSPAPER`.
     
     </div>
+    
+    When `MEDI` is a substructure of a `https://gedcom.io/terms/v7/FORM`, it is
+    recommended that its payload describes the medium from which it was derived.
+    
+    <div class="example">
+    
+    Consider a digital photo in a multimedia record; for this asset, the
+    `FORM`.`MEDI` is recommended to be `PHOTO` rather than `ELECTRONIC`.
+    
+    </div>
 
 label: 'Medium'