Many groups used variations of the rapper-vocalist theme, such as a German rapper with American singers (Real McCoy), or the use of reggae rap as in Ice MC and Fun Factory, or combination of rapper and reggae vocalist like in the "Life in the Streets" album, or scat singing as in Scatman John. Solo singing artists such as Alexia, Dr. Alban, Haddaway, Corona, Playahitty, Whigfield, Double You, and DJ BoBo also contributed to the genre. Some acts like the Swedish dance-pop originated group Ace of Base use more pop vocals rather than rap/soul vocals along with Eurodance sound. Pop vocals were particularly popular in the late 1990s Eurodance productions. The Swedish group Rednex also introduced American country music elements into the sound.