- BRAMMERTZ S., DE VRESSE S., THYS J., "Collaboration policière transfrontalière" (Cross-border Police Cooperation), study carried out under the supervision of TULKENS F. and VAN OUTRIVE L., Minister of the Interior, National General Police, pub.
- BRAMMERTZ S., DE VRESSE S., THYS J., "Collaboration policière transfrontalière" (Cross-border Police Cooperation), study carried out under the supervision of TULKENS F. and VAN OUTRIVE L., Minister of the Interior, National General Police, pub.