Carl Meißner; Henry William Auden (1894),Latin Phrase-Book[1], London:Macmillan and Co.
an impassable road:iter impeditum
impedio inRamminger, Johann (16 July 2016 (last accessed)),Neulateinische Wortliste: Ein Wörterbuch des Lateinischen von Petrarca bis 1700[2], pre-publication website, 2005-2016
Roberts, Edward A. (2014),A Comprehensive Etymological Dictionary of the Spanish Language with Families of Words based on Indo-European Roots, Xlibris Corporation,→ISBN