University of Oklahoma. Bureau of Business Research. Economic development series. University of Oklahoma, Bureau of Business Research.
Παραπομπή σε μορφή Chicago (17η εκδ.)University of Oklahoma. Bureau of Business Research. Economic Development Series. Norman: University of Oklahoma, Bureau of Business Research.
Παραπομπή σε μορφή MLA (8th εκδ.)University of Oklahoma. Bureau of Business Research. Economic Development Series. University of Oklahoma, Bureau of Business Research.
Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.