Sort of a vs Sort of

“What sort of a wife is she?”
“What sort of wife is she?”

Which of the sentences is incorrect?

I would definitely choose the latter to be the incorrect one given the grammar fact (the way I interprete the rule) that a singular noun must be always preceded by either a direct or indirect article, but reading on somebody`s grammar found out that the first one is considered grammatically wrong, if so, why would it be wrong?

God Bless you all.
Cisco.

Hi Cisco

Both versions are in use. However, your second sentence (i.e. without the indefinite article) is probably far more commonly used.

Here is a quote from the novel Pride and Prejudice:

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Amy, you are very nice. Thanks for the assistance, but above all, thanks for the time that you have taken to help me, I cannot ever repay your kidness, from the bottom of my heart, THANK YOU. God Bless you.

Sincerely, Cisco.

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You’re very welcome, Cisco.

Keep up the great work!
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