References
- Sjödin I. Psychotherapy in peptic ulcer disease: A controlled outcome study. Acta Psychiatr Scand 1983; 67, suppl 307
- Svedlund J. Psychotherapy in irritable bowel syndrome: A controlled outcome study. Acta Psychiatr Scand 1983; 67, suppl 306
- Campbell D T, Stanley JC. Experimental and quasi-experimental designs for research. Rand McNally College Publishing Company, Chicago 1963