There were 4 illustrations found for epithet widgrenii
 
309476 714553 Oncidium widgrenii Lindl. C.F.P. von Martius, A.G. Eichler, I. Urban, Fl. Bras., vol. 3(6): fasicle 128, (Orchidaceae, tribus XVIII - XXII, addenda et emendanda): t. 66 (1905)
 
309512 714553 Oncidium widgrenii Lindl. C.F.P. von Martius, A.G. Eichler, I. Urban, Fl. Bras., vol. 3(6): fasicle 128, (Orchidaceae, tribus XVIII - XXII, addenda et emendanda): t. 68 (1905)