If no author is given or a work is anonymous, cite the work by its title. Use the full title if it is brief or a shortened version if it is longer. When abbreviating a title, begin with the word by which it is alphabetized:
A Glossary of Literary Terms Used in Nineteenth Century Literary Criticism becomes Glossary of Literary Terms
If the title of the work is already used in your text, simply include the page number in your parenthetical citation.