Project Server and SQL Server CALs

[Lee]

I have a question on licensing and CALs: If I want to run Project Server with
Project Professional and Web Access Clients, I need the CALs for Web Access
Clients only as Project Professional comes with the Project Server CAL for
that copy of Professional. Is this correct?

Also, With the SQL Server back end, what licenses / CALS do I need for SQL
Server?

Thanks for all and any help!