Kryptogamae Exsiccatae Editae A Museo Palatino Vindobonensi [2601-3200], Keissler, K. von [2601 - 3200]
Usually cited as "Anonymous"; author changes given according Pfister (1985). For more detailed information see Stevenson (1971) p. 239. There are several numbers used again for issuing the same species in later times without any note on the labels.