Looking for an artist

I am looking for the name of the artist that sings an oldie song called The Letter. Some of the lyrics are "A letter has come, and now I must join the boys in Vietnam. I have searched everywhere, maybe someone can help. Thanks

"He'll Be Back" by The Players

Thanks kaos, I have been looking for that name for a long time. Maybe you can help with this next one. The lyrics have words of "I want to get married but we're so young" Thanks again

"I'm So Young" by the Beach Boys?

I have a girlfriend
She says I'm her only one
We wanna get married
But we're so young
So young
Can't marry no one
They say our love is
Just a teenage affection
But no one knows
Our hearts' direction

So young
Can't marry no one
I'm I'm I'm so young
hey,hey,hey so young
I'm I'm I'm so young
Can't marry no one, no one

Pretty soon now
I'll go to see
Their mother's baby
Will have seen the last of me
So young
Can't marry no one, no one

Can't marry no one
Can't marry no one
Can't marry no one
Can't marry no one
Can't marry no one
Can't marry no one

yes thats the one!!!! but it's not by the Beach Boys. Somebody else sings it. I found it on a music site but it doesn't have the artist. Thanks so much

@TinaD661: Beach Boys sings this too
according to Wikipedia: original singer is The Students
covers are made by: Rosie and the Originals, the The Del-Vikings, the Beach Boys, and by The Ronettes (as "So Young").

I didn't mean to imply the Beach Boys did not sing it. But the one that I want is a doo wap version and probably by The Students. Your help is greatly appreciated. Couldn't have found it on my own. Thanks

yes, you are right, Students did the doo wap
i'm glad, you have found your song