Upon arriving in Cologne, Ligeti began to write electronic music alongside Karlheinz Stockhausen and Gottfried Michael Koenig at the electronic studio of West German Radio (WDR). He completed only two works in this medium, however—the pieces "Glissandi" (1957) and "Artikulation" (1958)—before returning to instrumental music. A third work, originally entitled "Atmosphères" but later known as "Pièce électronique Nr. 3", was planned, but the technical limitations of the time prevented Ligeti from realizing it completely. It was finally realised in 1996 by the Dutch composers Kees Tazelaar and Johan van Kreij of the Institute of Sonology.