When a quotation ends a sentence and the parenthetical citation is at the end, the period should come after the citation. Additionally, there are separate rules for long quotations. When a quote with ...

Place the period outside the quotation marks if a parenthetical citation appears after a direct quotation. Example: Their focus on writing as a discipline can be linked with Faigley's (1986) belief ...

The comma is between the tagline and dialogue. With dialogue ending a sentence, the period should stay within the quotation marks. This pertains to dialogue without parenthetical citation at the end ...