de Leeuw, K. M. M. (2000). Cryptology and statecraft in the Dutch Republic. [Thesis, fully internal, Universiteit van Amsterdam].
Bergstra, J. A., & Loots, M. E. (1999). Software mechanics for java multi-threading. Technical Report P9906. WINS (oud WINS).
Bergstra, J. A., & Ponse, A. (1999). Process algebra with five-valued logic. Australian Computer Science Communications, 21, 128-143.
Krikhaar, R. (1999). Software architecture reconstruction. [Thesis, externally prepared, Universiteit van Amsterdam].
Bergstra, J. A., & Stefanescu, G. (1998). Network algebra with demonic relation operators. Revue Roumaine de Mathematiques pure et appliquees, Tome 42(5-6), 57-88.
Bergstra, J. A., & Klint, P. (1998). Theorie en logica eruit, het bedrijfsleven erin. Automatisering gids.
Bergstra, J. A., & Klint, P. (1998). Informatica moet eigen weg kiezen. Automatisering gids.
Bergstra, J. A., & Ponse, A. (1998). Grid protocol specifications. In Propects for hardware foundations (pp. 278-309). (LNCS; No. 1546). Springer Verlag GmbH.
Bergstra, J. A., & Ponse, A. (1998). Two recursive generalisations of iteration in process algebra. WINS (oud WINS).
Bergstra, J. A., & Loots, M. E. (1998). Program algebra for component code. WINS (oud WINS).