Sputnik first appeared in Captain America #352-353 (April-May 1989), and was created by Mark Gruenwald and Kieron Dwyer.
The character subsequently appears as Vostok in Avengers #319-324 (July-October 1990), Incredible Hulk #393 (May 1992), Soviet Super-Soldiers #1 (November 1992), Quasar #54 (January 1994), Iron Man #9-10 (October-November 1998), Maximum Security 33 (January 2001), and Thunderbolts #57 (December 2001).