Issue How does awstats display stats for domain alias?

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Hello community.
I use latest Plesk 12.5 version on a ubuntu server. This includes also Awstats.
For some of my domains I added one/two/three alias domains with a redirect to the main domain. Now, I had a look on awstats and can not find any entry which shows me how often the domain alias was requested.
I expected a select box where I can choose the domain.
My question is, how can I see how often an alias of the domain is called on my server?
Is there any setting I have to add in Plesk?
Thanks a lot in advance!