In Latin Prose Composition by John Arbuthnot Nairn (Cambridge UP, 1926; p. 5 of "Versions" section), I find the following as a translation of Shakespeare's "Friends, Romans, countrymen, lend me your ears":
Populus Romanus Quiritium, amicique et cives mei, benigne me attenteque audiatis.
Is this correct Latin? It seems to me that Populus Romanus Quiritium needs to be vocative. But Nairn was an eminent Latinist and I have not so far found any other errors in his book, and it's a little hard to believe that he would have made such an elementary blunder. I've searched for the phrase Populus Romanus Quiritium but have not been able to find it used in direct address (while on the other hand Cicero uses popule Romane in the vocative).
Is there any possible justification for the nominatives here?