Flicking through it, I found that the ninth song in the fourth book - sorry, liber iv, carmen ix - is entitled "Ad Lollium". And, being currently fond of Troilus and Criseyde, I naturally said "Ha!" to myself. Because Chaucer's poem is a translation (much adapted) of Boccaccio's Filostrato, but he never acknowledges Boccaccio by name. Instead, he refers to other more ancient authorities on the Trojan war, particularly "myn auctour called Lollius" (I.394). Not attributing it to Boccaccio is understandable - after all, a contemporary author isn't much of an "auctoritee" compared to an ancient Roman. But who was the Lollius who got the credit instead?
Many theories have been spun to explain this roundabout attribution to a non-existent classical author, including the possibility that Chaucer was just having a joke at the expense of everyone who searched wildly and often inaccurately for some kind of authority to support their own words (or just fill up space in a line). But according to Horatius, a Lollius did exist, even if he never actually wrote about Troy. Would Chaucer have known the poem? Well, probably, since Horatius was (to the best of my knowledge) reasonably well read in Chaucer's time. But the poem, so far as I can make out, doesn't refer to Lollius as an author, though it includes references to "Homerus" (7), "Helene" (16), "Hector", "Deiphobus" (both 22) and others. So why Lollius, Chaucer, out of the many people to whom Horatius addressed his songs?
The Riverside Chaucer, naturally, solved the question:
The question of Lollius' identity has aroused much speculation.... Kittredge argued that Chaucer erroneously believed that there was a Lollius who was an authority on the Trojan War, and he accepted a suggestion ... that Chaucer had followed some medieval misunderstanding of the opening of Horace, Epist. 1.2.1-2: "Trojani belli scriptorem, Maxime Lolli, / Dum tu declamas Romae, Praeneste relegi" (While you declaim at Rome, Maximus Lollius, I have been reading again at Praeneste the writer of the Trojan War - that is, Homer). Reading "scriptorem" as "scriptorum" (and taking "Maxime" as an adjective rather than a proper noun) would give "Lollius, greatest of authors of the Trojan War".So imagine my delight when I turned to the epistle in question in this volume of Horatius and found the following lines:
Trojani belli scriptorum, maxime Lolli,Not just a mediaeval error, it seems!
Dum tu declamas Romae, Praeneste relegi;
Still. Poor Boccaccio should have sued for copyright.
 Ed. H. H. Milman (London: John Murray, 1853)
 Or possibly aloud. I have been known to do this very loudly in quiet coffee shops. People are usually very kind and pretend nothing happened.