A user visits your website via Google (Referrer: "www.google.com") and starts with viewing the page "home". She afterwards views the pages "search" and "product view".
Changing themetric scopefor Page Impressions will have the effect that all Page Impressions in the visit are counted. In the example, this would yield 3 Page Impressions.
Pages Analysis(Navigation > Pages > Pages)
Changing themetric scopefor Qty Sources will have the effect that all referrers in the visit are counted. In the example, this would yield 3 Page Impressions.
Example for using this metric in a filter:
Show only visits where exactly two referrers were measured:
This includes the case that the same referrer has been measured 2 times.
The Auto scope is Visits. Alternatively, you could explicitly choose the scope Visits.