The Duty to Renegotiate an International Sales Contract under CISG in Case of Hardship and the Use of the Unidroit Principles - European Review of Private Law View The Duty to Renegotiate an International Sales Contract under CISG in Case of Hardship and the Use of the Unidroit Principles by - European Review of Private Law The Duty to Renegotiate an International Sales Contract under CISG in Case of Hardship and the Use of the Unidroit Principles 19 1 European Review of Private Law