Iliad 3.39 "Did you not, such as you are, get your following together and sail beyond the seas ? Did you not from your a far country carry off a lovely woman wedded among a people of warriors - to bring sorrow upon your father, your city, and your whole district, but joy to your enemies, and hang-dog shamefacedness to yourself? And now can you not dare face Menelaos and learn what manner of man he is whose wife you have stolen?" In terms of an event that occurs in the temporal run of the text, this is Hektor shaming Paris for his cowardice, but it refers to the series of events in which Paris sparked the war.

3.181 "The old man marveled at him and said, "Happy son of Atreus, child of good fortune. I see that the Achaeans are subject to you in great multitudes. When I was in Phrygia I saw much horsemen, the people of Otreus and of Mygdon, who were camping upon the banks of the river Sangarios; I was their ally, and with them when the Amazons, peers of men, came up against them, but even they were not so many as the Achaeans."

This, while more vague, seems to refer to Antenor allying with the Otrians and Mygdonians in a battle against the Amazons, but is again temporally irrelevant to the proceedings of book3 proper.

How do we identify moments like this, in which past events are obliquely referred to?