Fix typo

Author: shoheichura

README.md

@@ -27,7 +27,7 @@ Features include:
   - Get all fields in a data source
   - Get all fields in use by certain sheets in a workbook
 
-For Hyper files, take a look a the [Tableau Hyper API](https://help.tableau.com/current/api/hyper_api/en-us/index.html).
+For Hyper files, take a look at the [Tableau Hyper API](https://help.tableau.com/current/api/hyper_api/en-us/index.html).
 
 We don't support creating files from scratch, adding extracts into workbooks or data sources, or updating field information