Utilizing Directory URL: for creating a "Phonebook"

I am using FreePBX 2.10.xx
I am attempting to create and implement a “PhoneBook” for a extension
I see that there is a place to insert a URL address pointing to "Directory URL:"
Is there a “template” available to show me the syntax needed to create the correct file (and proper file name)?

Thanks

What phones are u using ? Try googling, it does help. I’ve got blog entries for yealinks and cisco

I am using Cisco 7960 SIP