Containers
In addition to standardizing the core elements required for a citation, MLA 8th also introduces the concept of containers. MLA states:
"The concept of containers is crucial to MLA style. When the source being documented forms part of a larger whole, the larger whole can be thought of as a container that holds the source. For example, a short story may be contained in an anthology. The short story is the source, and the anthology is the container."
(https://style.mla.org/works-cited-a-quick-guide/)
When citing, the title of the container is generally italicized and is followed by a comma. For example, for articles in journals, the journal is the container that holds the article.
Baron, Naomi S. "Redefining Reading: The Impact of Digital Communications Media." PMLA, vol. 128, no. 1, Jan. 2013, pp. 193-200.
(MLA Handbook, 8th ed., p. 30)
Sometimes the source that you are citing has two containers. For example, for articles found in a database, the first container is the name of the journal. The second container is the database where you found the article. Please see the example below.
(https://style.mla.org/works-cited-a-quick-guide-journal/)
Academic Search Complete
search.ebscohost.com/login.aspx?direct=true&db=f5h&AN=24093790&site=ehost-live.
“Between Image and Word, Color, and Time: Jacob Lawrence’s The Migration Series.” African American Review, vol. 40, no. 3, 2006, pp. 571-86. Academic Search Complete, search.ebscohost.com/login.aspx?direct=true&db=f5h&AN=24093790&site=ehost-live.