APA (7th ed.) Zitazioa
Bals, L. (2008). Sourcing of services: International aspects and complex categories. Gabler.
Chicago Style (17th ed.) Zitazioa
Bals, Lydia. Sourcing of Services: International Aspects and Complex Categories. Wiesbaden: Gabler, 2008.
MLA (9th ed.) Zitazioa
Bals, Lydia. Sourcing of Services: International Aspects and Complex Categories. Gabler, 2008.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.