To add an external source to the list of sources in use, follow these steps:
1.Open the list of sources.
2.In the External data sources window, click Add source.
3.In the file manager window, select the source file.
4.In the Select sheet window, choose a sheet from the external document from the list and click OK. Clear the The first line of the data range contains titles checkbox if you do not want to use the first row as a title.
The selected source will appear in the External data sources list, after which you can close the window in any way you like.