Although it is not generally necessary to indicate that a work appears in a special issue of a journal, you can cite special issues by following the MLA format template. Include the same information you would for an article in a regular issue, adding the special issue’s title, a comma, and the phrase “special issue of” before the journal’s title in the “Title of Container” slot:
Charney, Michael W. “Literary Culture on the Burma-Manipur Frontier in the Eighteenth and Nineteenth Centuries.” Literary Cultures at the Frontiers: Literature and Identity in the Early Modern World, special issue of The Medieval History Journal, . . .
Published 5 January 2018