Riddle, D. (2001). Innovating for success in the export of services: A handbook. International Trade Centre.
Chicago-viite (17. p.)Riddle, Dorothy. Innovating for Success in the Export of Services: A Handbook. Geneva: International Trade Centre, 2001.
MLA-viite (9. p.)Riddle, Dorothy. Innovating for Success in the Export of Services: A Handbook. International Trade Centre, 2001.
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