the single prologue of exo-k and exo-m, "what is love" was released on january 30, 2012 in south korea and mainland china. the single was positioned at number 88 on the korean chart gaon single chart. on march 9, the group released its second single prologue entitled «history», which was written and produced by thomas troelsen and remee. the single was positioned at number 78 in gaon single chart and number 6 on china's sina music chart. a concert by the group took place at the olympic stadium in seoul on march 31. approximately 3,000 fans of 8,000 were selected to attend. a second concert was held in the great hall of beijing university of economics and business, april 1. both subunits released his third debut single entitled "mama" april 8 followed by an ep of the same name the next day. the two subunits promoted the album separately in two countries. on april 8, one day before the release of the ep, exo-k had their debut performance on the musical program of south korea "inkigayo", while exo-m made its debut in china awards 12th yinyue fengyun bang awards the same day. the mandarin version of "mama" headlined at the number 2 in the chinese chart sina.com, while the korean version was positioned number 1 of gaon albums chart and number 8 on the billboard world albums chart. the mandarin version of the music video "mama" reached number 1 on the websites of chinese transmission, while the korean version was ranked number 7 on youtube's global chart. at the end of april, exo-m appeared as guests in the concert of super junior "super show 4" in jakarta, indonesia. in november 2012, exo won an award as best new group of asian artists in 2012 mnet asian music awards. exo-k three nominations in 27th golden disk awards gaining in the newcomer category. exo-m awarded the most popular group in 2013 top chinese music awards.