Simultaneous optimisation of test and maintenance intervals of given components using non-homogenous semi-Markov models. - Günter Becker; Janet Nagel; Leonidas Camarinopoulos; George Zioutas (J. Oper. Res. Soc., 2001)

Developing Different Environmental Database Applications Using a Generic Software. - Ulrich Hussels; Matthias Lüttgert; Janet Nagel (EnviroInfo, 2003)