format Chicago 16th - coma in the name of the journal article

Hello everyone,

I am using Chicago 16th Ed. for my writing. However, I do not understand why there is a coma at the end of my quote on the article. For example: Helen Quane, “The Significance of an Evolving Relationship: ASEAN States and the Global Human Rights Mechanisms,” Human Rights Law Review 15 (2015)

If anyone can help me I would be grateful!

Cé