Wright, H. F. Observational Methods in Child Study. In: Mus-sen, P. H. "Ed.", I٩٦٠.
Wurtman, R.J. Alzheimer.htm's Disease. Scientific American, January ١٩٨٥.
Yankclovich, D. New Roles: Searching for Self-fulfillment in a World Turned Upside Down. New York: Random House. ١٩٨١.
Zung, W. W. K. Affective Disorders. In: Busse, E.W. & Blas-er, D. "Eds." Handbook of Geraiatric Psychiatry. New York: Van Nostrand Rinehold, ١٩٨٠.