"firmly attributed" — Kollokationen-Wörterbuch Englisch

firmly attributed Kollokation
Automatische Übersetzung (wir garantieren seine Korrektheit nicht): stanowczo przypisać
  1. attribute Verb + firmly Adverb
    Schwache Kollokation

    The drawing was firmly attributed to the artist when it was last sold in Munich in 1938, but was believed lost in the last war.