Direct microextraction for red lakes detection in painting layers by Raman spectroscopy Silvia Innocenti, Marilena Ricci, Giancarlo Lanterna, Raffaella Fontana, Jana Striova and Maurizio Becucci Eur. Phys. J. Plus, 136 10 (2021) 1081 Published online: 28 October 2021 DOI: 10.1140/epjp/s13360-021-02069-5