Doyle, R. E. (1998). Essential skills and strategies in the helping process (2nd ed.). Brooks/Cole.
Cita Chicago (17th ed.)Doyle, Robert E. Essential Skills and Strategies in the Helping Process. 2nd ed. Pacific Grove: Brooks/Cole, 1998.
Cita MLA (9th ed.)Doyle, Robert E. Essential Skills and Strategies in the Helping Process. 2nd ed. Brooks/Cole, 1998.
Atenció: Aquestes cites poden no estar 100% correctes.