The ancient Greek poem besides Works and Days that also mentions Pandora is Theogony.
Theogony is a poem attributed to Hesiod that presents the origins, births, and relationships of the Greek gods. It includes an account of Pandora’s creation and her connection to the punishment of humanity. Works and Days gives the more developed narrative involving the jar and the release of troubles.
The two poems are among the earliest surviving Greek literary sources for the myth. They are not identical in emphasis or wording, which is why modern retellings can differ about Pandora’s role and the meaning of what remained in the jar.
The Iliad and Odyssey are also foundational ancient Greek poems, but they are attributed to Homer and do not provide the same early Pandora account. Argonautica is a much later Greek epic associated with Apollonius Rhodius, so it is not the relevant Hesiodic source.