1. Periodic processes: a variational approach;Horn,1967
2. Optimal control of multi-variable periodic processes;Fjeld,1968
3. An application of the theorem of relaxed control to the problem of increasing catalyst selectivity;Horn;J. Optim. Theory Appl,1968
4. On the steady-state relation between top product concentration and distillate flow rate in two components distillation columns;Locatelli;Int. Report Istituto di Elettrotecnica ed Elettronica del Politecnico di Milano,1969