diff --git a/affiliations-tools/swagger.json b/affiliations-tools/swagger.json
index 7ebe3e0..f214376 100644
--- a/affiliations-tools/swagger.json
+++ b/affiliations-tools/swagger.json
@@ -10,8 +10,11 @@
       "type": "object",
       "properties": {
         "xPublicationDate": {
-          "type": "string",
-          "format": "date"
+          "type": "array",
+          "items": {
+            "type": "string",
+            "format": "date"
+          }
         },
         "authors": {
           "type": "array",
@@ -31,8 +34,11 @@
       "type": "object",
       "properties": {
         "xPublicationDate": {
-          "type": "string",
-          "format": "date"
+          "type": "array",
+          "items": {
+            "type": "string",
+            "format": "date"
+          }
         },
         "authors": {
           "type": "array",