json/v1.0/email.json in sk_api_schema-0.0.15 vs json/v1.0/email.json in sk_api_schema-0.0.16

@@ -118,11 +118,11 @@
           "description": "All objects updated on/before the date"
         },
         "sort_by":{
           "title" : "Sort by",
           "description": "Sort the results by the given field => number",
-          "enum":['created_at', 'updated_at'],
-          "type": 'string'
+          "enum":["created_at", "updated_at"],
+          "type": "string"
         },
         "sort":{
           "title" : "Sort",
           "enum":["ASC","DESC"],
           "description": "Sort the results in ASC or DESC"
\ No newline at end of file