Check the inside covers of your manga for the publication and authorial information. If you can't find it, go to Anime News Network's Manga Encyclopedia Web site and find the manga you're citing in the list. The manga's page will list all the data you need to know to properly cite the work.
Use the following format if you're writing in MLA style:
Author(s). Italicized Title. Trans. Translator(s). Issue (Year): pages. Medium of publication.
Naruto, for example, would look like this:
Masashi Kishimoto. Naruto. Trans. Katy Bridges, Mari Morimoto. GN 30 (2008): 189-190. Print.
Use the following format if you're writing in APA style:
Author(s) (Year). Italicized Title. (Translator(s), Trans.) Issue, pages.
Hellsing, for example, would look like this:
Kouta Hirano (2005). Hellsing. (Duane Johnson, Trans.). GN 7, 110-115.
Use the following format if you're writing in Chicago style as a note citation:
Author(s), Italicized Title, trans. Translator(s), Issue (Year): pages.
Use this format if you're citing the manga in your bibliography:
Author(s). Italicized Title. Translated by Translator(s). Issue (Year): pages.
Death Note, for example, would look like this as a footnote:
1. Tsugumi Ohba, Death Note, trans. Pookie Rolf, GN 5 (2006): 97-102.
And like this in a bibliography:
Tsugumi Ohba. Death Note. Translated by Pookie Rolf. GN 12 (2007): 97-102.