The Standard Model (SM) provides an incomplete description of elementary particles and their interactions, therefore an extension or modification is necessary. There are many proposed extensions with added particles to the SM to complement its shortcomings, but so far none of them have been directly detected. Experiments searching for processes with a violation of flavour are currently being done to measure the branching ratios of such processes and use the data to constrain theoretical extensions of the SM.

In this project we chose a model with three Higgs doublets and an S3 symmetry which have been studied before with interesting theoretical results and we wanted to expand the analysis into finding sources of lepton flavour violation for their phenomenological implications.