Billis, Emmanouil Otto Hahn Research Group on Alternative and Informal Systems of Crime Control and Criminal Justice, Max Planck Institute for the Study of Crime, Security and Law, Max Planck Society;
http://dx.doi.org/10.5040/9781509938636 (Any fulltext)
Billis, E., Knust, N., & Rui, J. P. (Eds.). (2021). Proportionality in crime control and criminal justice. Oxford: Hart Publishing. doi:10.5040/9781509938636.