Contini, S., Copelli, S., Raboni, M., Torretta, V., Sala Cattaneo, C., & Rota, R. (2013). IEC 61508: Effect of Test Policy on the Probability of Failure on Demand of Safety Instrumented Systems. Chemical Engineering Transactions, 33, 487-492. https://doi.org/10.3303/CET1333082