The Wisconsin GF-126B Certificate of Appearance (Subpoena) is a legal document that is used to compel a witness to appear at a court hearing or trial. This document is issued by the court to a witness who is required to give evidence or testimony in court. It is also known as a subpoena. The Wisconsin GF-126B Certificate of Appearance (Subpoena) has two types: the Subpoena Ducks Cecum and the Subpoena Ad Testificandum. The Subpoena Ducks Cecum requires the witness to bring certain documents with them to court, while the Subpoena Ad Testificandum requires the witness to appear and provide testimony. The Wisconsin GF-126B Certificate of Appearance (Subpoena) must be served to the witness in person by a law enforcement officer or other authorized party. The document must include the name of the court, the name of the witness, and the date and time of the hearing. The witness must appear in court at the specified date and time or risk being held in contempt of court.