Drobnig, Ulrich MPI for Comparative and International Private Law, Max Planck Society;
https://max-eup2012.mpipriv.de/index.php/Suretyship_(Modern_Law) (Any fulltext)
Drobnig, U. (2012). Suretyship (Modern Law). In J. Basedow, K. J. Hopt, & R. Zimmermann (Eds.), The Max Planck Encyclopedia of European private law (pp. 1640-1643). Oxford: Oxford University Press.