Hungary 1851 Underpaid Envelope to Austria

bearing Austria Yvert 6, 6kr Brown tied by Pesth datestamp, underpaid with TAX handstamp instructional "Felendes Porto 3 / Zutaxe 3 / Summe 6" routed via Wien with "Bruck A.D.M. 22. Aug", arrival on reverse, Very fine item from the Austrian Post Office. (pt)    ID: 14038