The Letter - S3-E21
Character mistake: When Lippman is recounting his conversation with his accountant, he mentions that the accountant, a man, gave the tickets to "her daughter."
The Letter - S3-E21
Continuity mistake: While George is talking to Nina about the painting, Jerry can be seen taking a bottle of water from the refrigerator. He's then seen holding the bottle when buzzing up Elaine, but then when talking to Nina about the "pop-in", the bottle's gone. It's then back in the next shot when Nina says she's leaving. (00:15:13 - 00:16:00)
Answer: The name is Delores. He shouts that name at the end of the episode. Then in a later episode, "The Foundation", he runs into her. And he repeatedly calls her Delores.