TY  - RPRT
TI  - Evolving combinatorial problem instances that are difficult to solve.
AU  - Jano I van Hemert
PY  - 2006
DO  - 10.1162/evco.2006.14.4.433
UR  - https://pubmed.ncbi.nlm.nih.gov/17109606/
ID  - 17109606
ER  -