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Argentine cuarteto band
Tru-la-lá is one of the best known cuarteto bands in Argentina. The band's main singer for many years was Gary, "voice of an angel".
References
Revista de música latinoamericana Vol.25 2004 p245 "In chapter 5 Florine analyses the group dynamics and cultures of six cuarteto bands: Chébere, La Band del "Negro" Videla, Tru-la-lá, Gary, Santamarina, and Carlitos "La Mona" Jimenez."