%0 Journal Article %T Incentive contract design for internet referral services: cost per click vs cost per sale %A Zhou, Chi %A Xu, Geni %A Liu, Zhibing %J Kybernetes %V 49 %N 2 %P 601-626 %@ 0368-492X %D 2019-06-28 %I Emerald Group Publishing Limited %~ DeepDyve