3V3D:
reference: Improving the Second-Order Nonlinear Optical Response of Fluorescent Proteins: The Symmetry Argument., De Meulenaere E, Nguyen Bich N, de Wergifosse M, Van Hecke K, Van Meervelt L, Vanderleyden J, Champagne B, Clays K, J Am Chem Soc. 2013 Mar 1. PMID: 23406416

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