Barrett-Lennard, G. T. (1998). Carl Rogers' helping system: Journey and substance. Sage.
Chicago Style (17th ed.) CitationBarrett-Lennard, Godfrey T. Carl Rogers' Helping System: Journey and Substance. London [etc.]: Sage, 1998.
MLA (9th ed.) CitationBarrett-Lennard, Godfrey T. Carl Rogers' Helping System: Journey and Substance. Sage, 1998.
Warning: These citations may not always be 100% accurate.