A. M. Darsono, C. C. Toh, S. Saat, N. A. Manap, M. M. Ibrahim, and M. I. Ahmad, “β-Divergence Two-Dimensional Nonnegative Matrix Factorization with Sparseness Constraints for Biomedical Signal Separation”, JTEC, vol. 9, no. 2-6, pp. 7–10, Jun. 2017.