Cover of the same song originally launched by: Adolphe Adam
United States of America (USA), Canada, Mexico, India and Pakistan, have not (yet) signed the MCPS/PRS Agreement
For that reason, any Cover song, cannot be sold on the territory of the above Countries, by services as iTunes, Spotify, Amazon etc, if a quite important amount of money for the License, is not upfront payed to Harry Fox Agency (HFA)
In the case you are resident in one of the above Countries and you want to buy any of the Cover-songs, you can change the settings of your iTunes, Spotify, Amazon to choose any of the Countries not mentioned above, and to provide to the purchasing
In this way, the Rights are correctly payed out to the Authors/Composers/Copyright holders by the various Rights Agencies (SABAM, SIAE, GEMA, SACEM, PRS, etc) and you can legally enjoy the music.