APA

Callahan J. C., . (1988). Ethical issues in professional life. New York: Oxford University Press.

Chicago

Callahan Joan C, . 1988. Ethical issues in professional life. New York: Oxford University Press.

Harvard

Callahan J. C., . (1988). Ethical issues in professional life. New York: Oxford University Press.

MLA

Callahan Joan C, . Ethical issues in professional life. New York: Oxford University Press. 1988.