Sommerfeld, M., & Haller, O. (1987). The normalization of persons with mental handicaps and mental illness: A field study. The Vocational and Rehabilitation Research Institute.
Chicago-viite (17. p.)Sommerfeld, Marian, ja Otto Haller. The Normalization of Persons with Mental Handicaps and Mental Illness: A Field Study. Calgary, Alta.: The Vocational and Rehabilitation Research Institute, 1987.
MLA-viite (8. p.)Sommerfeld, Marian, ja Otto Haller. The Normalization of Persons with Mental Handicaps and Mental Illness: A Field Study. The Vocational and Rehabilitation Research Institute, 1987.
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