Section 673.4011 - Signature(1) A person is not liable on an instrument unless:(a) The person signed the instrument; or(b) The person is represented by an agent or representative who signed the instrument and the signature is binding on the represented person under s. 673.4021.(2) A signature may be made: (a) Manually or by means of a device or machine; and(b) By the use of any name, including a trade or assumed name, or by a word, mark, or symbol executed or adopted by a person with present intention to authenticate a writing.