Ball, E. L. C. E. (1978). Leisure ser vices oreoaration: A competency based approach 1978. Prentice hall.
शिकागो स्टाइल उद्धरणBall, Edith L Cipriano,Robert E. Leisure Ser Vices Oreoaration: A Competency Based Approach 1978. NJ: Prentice hall, 1978.
एमएलए उद्धरणBall, Edith L Cipriano,Robert E. Leisure Ser Vices Oreoaration: A Competency Based Approach 1978. Prentice hall, 1978.
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