Question: Which cosmonaut, Franz Viehböck and Sigmund Jähn, visited the Mir space station in 1991 aboard Soyuz TM-13?
Sentence (from "Sigmund Jähn"): Sigmund Werner Paul Jähn (born 13 February 1937) is a German cosmonaut and pilot, who in 1978 became the first East German (and German native) to fly in space as part of the Soviet Union's Interkosmos programme.
Relevant evidence: Yes