What was written and performed by Viggo Sommer, Carsten Knudsen, and Uffe Rørbæk Madsen that resulted in invented phrases from the series to enter popular culture?
De Nattergale:  The group consists of Viggo Sommer, Carsten Knudsen and Uffe Rørbæk Madsen. The Julekalender: The Julekalender (The Christmas Calendar) was a "julekalender" that ran at Christmas 1991 (a Norwegian version was made in 1994, and a Finnish version appeared in 1997). The Julekalender:  It was written and performed almost entirely by a trio of Danish comedy musicians called De Nattergale with financial and technical assistance from TV2, a Danish television company. The Julekalender:  It was hugely successful at the time, causing many invented phrases from the series to enter popular culture and was later released on VHS, and recently, DVD.
i don't know