"请在这儿签名。"

Translation: Please sign here.

[KX3.]

请在此签名 sounds more formal.

[NasuSamaruk0]

Yes, the given sentence 请在这儿签名 is used in conversation, even though both sentences are in polite form.

[Anon341685]

Just wondering, what's the difference between 这里 and 这儿 ?