Czech experimental underground group. Formed in 1973 by Pavel Zajíček and Milan Hlavsa. Like the Plastic People of the Universe, they were systematically persecuted by the communist regime. De facto disbanded in 1980 due to Zajíček’s forced emigration. Reactivated in 1992. Inactive since 2015 due to Pavel Zajíček's illness. Activity: 1973-1976, 1979-1980, 1992-2015.