Ultrafast Ultrasound Imaging as an Inverse Problem: Matrix-Free Sparse Image Reconstruction. - Besson, Adrien; Perdios, Dimitris; Martinez, Florian; Chen, Zhouye; Carrillo, Rafael E.; Arditi, Marcel; Wiaux, Yves; Thiran, Jean-Philippe (IEEE Transactions on Ultrasonics Ferroelectrics & Frequency Control, 2018)