The band followed up "Sturmvogel" with an album of 1950s and early 1960s rock'n'roll songs, "Rock ’n’ Roll Music", which was one of the band's top sellers in East Germany, in part due to the unavailability of the records by the original artists; it sold less well in the west. The band asked Chuck Berry himself for the lyrics to "Brown Eyed Handsome Man"; he replied that he had forgotten them. It was followed by the harder rocking "Perlenfischer" (Pearl Diver, 1977) and "10 Wilde Jahre" (10 Crazy Years, 1978), the latter of which included "Doch die Gitter schweigen" (Still The Prison Bars Are Silent, later recorded in English as "Prison Walls Are Silent"), an epic tune that was commissioned for celebrations of the GDR's 30th anniversary in 1979; its topic, a prisoner's longing to escape.