Gagnon, Louis, Meryem Yücel, Mathieu Dehaes, Robert Cooper, Katherine Perdue, Juliette Selb, Theodore Huppert, Richard Hoge, and David Boas. 2012. “Quantification of the Cortical Contribution to the NIRS Signal over the Motor Cortex Using Concurrent NIRS-FMRI Measurements”. Neuroimage 59 (4): 3933–3940.