diff --git a/previewers/betatest/js/ncml.js b/previewers/betatest/js/ncml.js
index 993e72d..15ef09a 100644
--- a/previewers/betatest/js/ncml.js
+++ b/previewers/betatest/js/ncml.js
@@ -9,7 +9,12 @@ function translateBaseHtmlPage() {
 
 function writeContent(fileUrl, file, title, authors) {
     addStandardPreviewHeader(file, title, authors);
-    var ncmlUrl = queryParams.get("siteUrl") + "/api/access/datafile/" + queryParams.get("fileid") + "/auxiliary/NcML/0.1";
+    var apiTokenOptional = "";
+    var apiToken = queryParams.get("key");
+    if (apiToken != null) {
+        apiTokenOptional = "?key=" + apiToken;
+    }
+    var ncmlUrl = queryParams.get("siteUrl") + "/api/access/datafile/" + queryParams.get("fileid") + "/auxiliary/NcML/0.1" + apiTokenOptional;
     // copied from text.js
     var whiteList = {
         a: ["title"],