Letter of Reference- Certified True Copy meaning

[karthnar]

Hi,

I have applied for my PR at Buffalo.
I was asked to provide a Letter of Reference from my employer about my job- as Certified True Copy.

What does Certified True Copy mean?

Do I have to notarize it by a Notary public OR will just the sign of the Manager be enough on the company letterhead.
If a Notary is needed, does the manager have to sign in front of the Notary.

Thanks for the help

C