Hill, G. E. (1965). Management and improvement of guidance. Appleton Century Crofts.
Chicago-viite (17. p.)Hill, George E. Management and Improvement of Guidance. Appleton Century Crofts, 1965.
MLA-viite (9. p.)Hill, George E. Management and Improvement of Guidance. Appleton Century Crofts, 1965.
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