Listen to The People United Will Never Be Defeated!: Variation 15. Flexible, like an improvisation online. The People United Will Never Be Defeated!: Variation 15. Flexible, like an improvisation is an Unknown language song and is sung by Ursula Oppens. The People United Will Never Be Defeated!: Variation 15. Flexible, like an improvisation, from the album Rzewski: The People United Will Never Be Defeated, was released in the year 2021. The duration of the song is 1:19. Download Unknown songs online from JioSaavn.