The detection of the sources is a mathematical problem that can find application in all that fields in which a mixture of different signals is available: it is widely used in acoustics, where different sounds can be received by multiple microphones, in decoding communication signals taken by antennas, in separation of seismic data and in image processing, just to name a few. In biomedical signal processing, the source detection can help in decoding the complex brain activity from electroencephalographic (EEG) data, in studying muscle activation from electromyographic (EMG) recordings and also finds some interesting applications in electrocardiography (ECG), where maternal and foetal ECG were considered as two distinct sources and thus were separated.