Using Lenses Attached to a Smartphone as a Macroscopic Early Warning Tool in the Illegal Timber Trade, in Particular for CITES-Listed Species - de Palacios, Paloma; G. Esteban, Luis; Gasson, Peter; Garcia-Fernandez, Francisco; de Marco, Antonio; Garcia-Iruela, Alberto; Garcia-Esteban, Lydia; Gonzalez-de-Vega, David; (Forests, 2020)