@article{Laurberg_2008,
    doi = {10.1155/2008/764206},
    url = {https://doi.org/10.1155%2F2008%2F764206},
    year = {2008},
    publisher = {Hindawi Limited},
    volume = {2008},
    pages = {1--9},
    author = {Hans Laurberg and Mads Gr{\ae}sb{\o}ll Christensen and Mark D. Plumbley and Lars Kai Hansen and S{\o}ren Holdt Jensen},
    title = {Theorems on Positive Data: On the Uniqueness of {NMF}},
    journal = {Computational Intelligence and Neuroscience}
}

@article{Laurberg_2008, doi = {10.1155/2008/764206}, url = {https://doi.org/10.1155%2F2008%2F764206}, year = {2008}, publisher = {Hindawi Limited}, volume = {2008}, pages = {1--9}, author = {Hans Laurberg and Mads Gr{\ae}sb{\o}ll Christensen and Mark D. Plumbley and Lars Kai Hansen and S{\o}ren Holdt Jensen}, title = {Theorems on Positive Data: On the Uniqueness of {NMF}}, journal = {Computational Intelligence and Neuroscience} }