Homer, in the Catalogue of Ships, and later, Apollodorus both describe the contributions of men and ships that various city-states made to the Greek expedition against Troy. As it stands, there are two separate sets of events in the events list; those drawn from Homer's description, and those drawn from Apollodorus' description. Homer and Apollodorus are clearly describing the same thing, although the information they provide is not identical.

For example, event 1078 cites Apollodorus saying that the Boeotians contributed 10 leaders and 40 ships, event 1406 cites Homer, who names the Boeotian leaders and says they contributed 50 ships with 120 men each. Homer and Apollodorus are referring to the same thing, and so we need to be able to see that, but we also need to be able to see and preserve the differences in their accounts.

Greg proposes two possible solutions. The first is to keep two separate events with two separate ids in the list of events, and to include a "same as" thing, so that the two events can be associated. This has the advantage of keeping each version of the events simply and unambiguously associated with its proper citation, but poses possibly insurmountable difficulties for when it comes time to incorporate ordered series of events into journeys (it will not be possible, it a journey, to have to contemporaneous and notionally identical events).

The second possible solution is to merge the two events under one id, and include bibl references for each of the sources (ie, Apollodorus, Homer, and whichever authors are added to the project in the future). The downside of this is that it could become difficult to present the information correctly, while also sorting out differences and showing clearly what info is contained in what source.

A third possibility is some system that combines these two possibilities, which would be dependent on subjective judgement of the difference of events.