Alessandro Ferreri received his Master's degree from the University of Palermo in 2016, after that he came to Paderborn for his PhD studies. Alessandro was funded by the SFB-TRR-142, project C02, and has obtained many important results concerning multiphoton linear and nonlinear interferometers and their integrated versions. His results have already been partly published in two papers (the third paper is currently under review). 25.03.2021 Alessandro successfully defended his PhD thesis entitled "Spectral engineering in multiphoton linear and nonlinear interferometry: the importance of being multimode". We congratulate Alessandro to his graduation!