Siehr, Kurt MPI for Comparative and International Private Law, Max Planck Society;
https://max-eup2012.mpipriv.de/index.php/Swiss_Code_of_Obligations_(OR) (Any fulltext)
Siehr, K. (2012). Swiss Code of Obligations (OR). In J. Basedow, K. J. Hopt, & R. Zimmermann (Eds.), The Max Planck Encyclopedia of European Private Law (pp. 1648-1649). Oxford: Oxford University Press.