Sideboard/credenza 1958 ID  

The top is original...
And the credenza is definitely Knoll.
But you should definitely sell it as there are no markings or labels apparently. I mean, what will your friends think?

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good one

Its real.
Sticker or no sticker, its Knoll all the way.

Idea
Just write "Knoll" on the back in black magic marker.

You could use one of them...
You could use one of them there wood burner tools to etch knoll on there real fancy like. I have seen that done before, and it looks sweeeeeettt!!

Lol @ lunchbox.
Lol @ lunchbox.