 The duo subsequently recorded "Mustt Mustt" (1990), a world fusion album credited only to Khan that features Khan's qawwali vocals with keyboard work from Brook.Considered a "secularized" or "Western" version of Khan's other Qawwali albums, it was critically acclaimed internationally and has been credited with leading Pakistani youth to discover Sufi religious music, qawwali.It was subsequently named one of the Top 100 albums of the 1990s by American music magazine "Alternative Press", and reached number 14 on the "Billboard" Top World Music Albums chart in 1991.