[en] A complete kinematics study of the ¹⁰B(³He,pααα) and ¹¹B(³He,dααα) reactions has been performed to study the multi-particle break-up of ¹²C resonances above the triple-alpha threshold. Four-particle coincidence detection gives us complete information on the direction and energy of the individual alpha particles from the decay of ¹²C, allowing us to extract new information on the structure of ¹²C which we shall present in this contribution. We have observed gamma de-excitation of the T = 1 15.11 MeV resonance using charged particle detectors, and have constructed Dalitz plots of the individual resonances in ¹²C using the complete kinematics information of the alpha particles which come from their break-up.