Ulbrich. (2021). Internal Crowdsourcing in Companies (1.). Springer International Publishing.
Čikaški stil citiranja (17. izdanje)Ulbrich. Internal Crowdsourcing in Companies. 1. Springer International Publishing, 2021.
MLA način citiranja (8. izdanje)Ulbrich. Internal Crowdsourcing in Companies. 1. Springer International Publishing, 2021.
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