A geometric approach to the maximum likelihood spectral estimator for sinusoids in noise. - C. Foias; Arthur E. Frazho; Peter J. Sherman (IEEE Trans. Inf. Theory, 1988)

A new approach for determining the spectral data of multichannel harmonic signals in noise. - C. Foias; Arthur E. Frazho; Peter J. Sherman (Math. Control. Signals Syst., 1990)