APA

Kennedy P., . (1993). Preparing for the twenty-first century. Nueva York: Random House.

Chicago

Kennedy Paul, . 1993. Preparing for the twenty-first century. Nueva York: Random House.

Harvard

Kennedy P., . (1993). Preparing for the twenty-first century. Nueva York: Random House.

MLA

Kennedy Paul, . Preparing for the twenty-first century. Nueva York: Random House. 1993.