One repository to check for notes about Norwegian parish records is the LDS Family History Library catalog.
Click on 'Catalog'
The next screen will offer a line which says
FamilySearch Catalog is in BETA. You can still visit the previous version.
Click on the blue words 'previous version'
On the next screen display choose 'Place search' by clicking on that button.
Enter 'Skoger' in the open box for Place and press Enter on your keyboard.
Choose the topic 'Church records' and read the notes they offer.
You can use that search for most parishes if you are spelling them to match the catalog entries. The older version of the online catalog currently offers more useful notes than the new BETA version.