an Entity references as follows:
American a cappella group Pentatonix has released 11 studio albums, five compilation albums, six extended plays (EPs), 34 singles and fiftyeight music videos. The group won the third season of The Sing-Off in 2011, and subsequently received a recording contract with Sony. In June 2012, Pentatonix released their first extended play, PTX, Volume 1 through Sony-owned independent record label Madison Gate Records. The EP debuted at number 14 on the US Billboard 200, selling 18,401 copies in its first week of sales. A Christmas EP, PTXmas, was released in November 2012. It was re-released in November 2013 with one of its new tracks, "Little Drummer Boy", debuting at number 13 on the US Billboard Hot 100 and charting in other countries such as Austria, Canada and New Zealand. The EP became the s