Can't get a PS script with a funtion to run

Hi,

I think I found a very usefull resource here but I'm unable to run it:

http://jeffwouters.nl/index.php/2013/09/powershell-function-to-get-ntfs-rights-on-a-folder-for-groups-and-users-recursive/

I've tried to run the script directly from a PS window, but whenever I try to execute a simple command, as from EXAMPLES, I get an error:

PS C:\Path> get-ntfspermissions -sharename '\\share\folder' -domain 'domain'

get-ntfspermissions : The term 'get-ntfspermissions' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included, 

The AD module loaded correctly. Any help please?