Send email to multiple users in Designer workflow

To send email to multiple users in Designer workflow using a Person or Group column.

Refer the links below.

http://rapidapplicationdevelopment.blogspot.com/2007/04/multi-value-columns-in-sharepoint.html

and

http://social.msdn.microsoft.com/forums/en-US/sharepointworkflow/thread/ebcb81ec-ba36-4a4c-bd01-26dc2c4d0913