Source Separation and Clustering of Phase-Locked Subspaces: Derivations   and Proofs
  Due to space limitations, our submission "Source Separation and Clustering of Phase-Locked Subspaces", accepted for publication on the IEEE Transactions on Neural Networks in 2011, presented some results without proof. Those proofs are provided in this paper. 
Miguel Almeida and Jan-Hendrik Schleimer and Jos\'e Bioucas-Dias and   Ricardo Vig\'ario
stat.ML