Kingsbury, D. (2002). Psychohistorical crisis (First mass market edition.). Tom Doherty Associates Book.
Cita Chicago Style (17a ed.)Kingsbury, Donald. Psychohistorical Crisis. First mass market edition. New York: Tom Doherty Associates Book, 2002.
Cita MLA (9a ed.)Kingsbury, Donald. Psychohistorical Crisis. First mass market edition. Tom Doherty Associates Book, 2002.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.