the letter on / of a date

[kwfine]

Dear teachers,

I am not very sure whether I should use on or of in the following sentence:

I am refering to your letter of / on May 12th, 2010...

Thanks


Kitty

 

[Rover_KE]

Use of.

Rover

 

[Fillet]

Use of.

Rover

I thought we use on for exact date?

 

[Rover_KE]

We say 'I am referring to your letter of May 12th 2010, which I received on May 14th'.

Rover

 

[MarieLina]

I have seen another option:
"I am refering to your letter dated May 12th, 2010"
is it correct?

 

[Rover_KE]

"I am referring to your letter dated May 12th, 2010"

is correct.

Rover