Hilton, M. (1993). Assessing the quality of service: Facilitator's guide. Aga Khan Foundation.
Chicago-viite (17. p.)Hilton, Martine. Assessing the Quality of Service: Facilitator's Guide. Washington, DC: Aga Khan Foundation, 1993.
MLA-viite (8. p.)Hilton, Martine. Assessing the Quality of Service: Facilitator's Guide. Aga Khan Foundation, 1993.
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