Soules, J. A. (1968). What can the matter be? Bell Telephone Laboratoires.
Cita Chicago (17th ed.)Soules, Jack A. What Can the Matter Be? Cresskill: Bell Telephone Laboratoires, 1968.
Cita MLA (9th ed.)Soules, Jack A. What Can the Matter Be? Bell Telephone Laboratoires, 1968.
Atenció: Aquestes cites poden no estar 100% correctes.